by preglacial valleys filled with glacial drift.
The " northern soils," which are glacial deposits more or less redistributed by water, are much less fertile as a rule, and consist of all possible varieties from a tough boulder clay to loose sand.
During the height of the glacial period the ice must have crossed the islands from E.
Slates and fine-grained sandstones appear here freely through the glacial drift.
Across it, at its head, are the glacial passes which lead to the foot of the Baroghil.
The glacial era has left abundant evidences in the topography of the state.
The soil is for the most part glacial drift, composed of clay, sand and gravel, and varying greatly in depth.
Glacial elimination has been less severe, or rather there has been, at any rate on the Atlantic side, an unimpeded return of Miocene types.
Chlorination in glacial acetic acid solution yields pentachlor-m-diketo-R-hexene (2) and, at a later stage, heptachlor-m-diketo-R-hexene (3).
In Pleistocene times, then, when there were prolonged glacial ages, the sea-level was lowered and at the same time there was a reduction in sea temperature, so that the rate of reproduction of the coral polypes, and so the growth of reefs, was diminished.
The glacial period effected in Europe a wholesale extermination of temperate types accompanied by a southern extension of the arctic flora.
It crystallizes in large plates, which melt at 98.5° C. and boil at 390° C. It is readily soluble in warm ether and in hot glacial acetic acid.
Numerous glacial marks, however, such as polished striated rocks, moraines, erratic blocks, &c., prove that the whole of Greenland, even the small islands and skerries outside the coast, has once been covered by the inland ice.
The alpine flora of Lebanon thus connects itself directly with the Oriental flora of lower altitudes, and is unrelated to the glacial flora of Europe and northern Asia.
The mountains both in Victoria and New South Wales were snow-capped, and glaciers flowed down their flanks and laid down Carboniferous glacial deposits, which are still preserved in basins that flank the mountain ranges, such as the famous conglomerates of Bacchus Marsh, Heathcote and the Loddon valley in Victoria, and cf Branxton and other localities in New South Wales.
During the glacial period many of the Nevada lakes attained a great size, several of them uniting to form the ancient " Lake Lahontan," in northwestern Nevada.
Kitson's work in Tasmania shows that there also the glacial beds may be correlated with the lower or Greta Coal Measures of New South Wales.
The disturbances among the underlying rocks of Ohio have been slight, and originally the surface was a plain only slightly undulating; stream dissection changed the region to one of numberless hills and valleys; glacial drift then filled up the valleys over large broken areas, forming the remarkably level till plains of northwestern Ohio; but at the same time other areas were broken by the uneven distribution of the drift, and south-eastern Ohio, which was unglaciated, retains its rugged hilly character, gradually merging with the typical plateau country farther S.E.
Greatest among modern Asiatic explorers (if we except Prjevalsky) is the brave Swede, Professor Sven Hedin, whose travels through the deserts of Takla Makan and Tibet, and whose investigations in the glacial regions of the Sarikol mountains, occupied him from 1894 to 1896.
Glacial action determined the direction and character of the rivers, made numerous swamps, and, by scouring out rock basins, damming rivers and leaving morainal hollows, determined the character and formation of the lakes, of which Minnesota has upwards of io,000, a number probably exceeding that of any other state in the Union.
- Topographically, Iowa lies wholly in the Prairie Plains Region, part of it having been overrun by the Great Ice Sheet of the Glacial epoch.
The age of the glacial deposits is later than the Glossopteris flora and occurs early in the time of the Gangamopteris flora.
Its ethnological value as indicating the existence of man on the Missouri in the glacial period is very doubtful, it being impossible accurately to determine the age of the deposits.
of navigable waters in the state), and, by falls and rapids caused by glacial displacement of rivers, furnishing a magnificent volume of water-power.
In the other parts of the state the soil is composed mainly of glacial drift, and is generally deep and fertile.
The lake really lies on the watershed between the two, and is probably a glacial relic.
Geographically the wheat-raising area extends across the entire south of the state - the Minnesota Valley and the Red River Valley - the rich glacial loam of which renders it one of the most productive wheat regions in the world.
Finally, the laws of distribution of animals over Siberia cannot be made out until the changes undergone by its surface during the Glacial and Lacustrine periods are well established and the Post-Tertiary fauna is better known The remarkable finds of Quaternary mammals about Omsk and their importance for the history of the Equidae are merely a slight indication of what may be expected in this field.
In the southern hemisphere the Palaeozoic flora appears ultimately to have been profoundly modified by a lowering of temperature and the existence of glacial conditions over a wide area.
This glacial material is in the form of a till or boulder clay, but in the lowlands, and especially along Narragansett Bay, it is generally overlaid by stratified drift deposited by glacial streams. Within Narragansett Bay are the numerous islands characteristic of an area which has suffered comparatively recent depression, the largest being Rhode Island (or Aquidneck), Conanicut Island and Prudence Island.
On reduction by sodium amalgam in glacial acetic acid solution they yield primary amines.
Many of them show glacial striae.
Acetophenoneoxime, C 6 H 5 C(:NOH) CH3, melts at 59° C. In glacial acetic acid solution, on the addition of concentrated sulphuric acid, it is converted into acetanilide.
And Reid has shown that during the glacial period the existing flora was replaced by an arctic one represented by such plants as Salix polaris, S.
There is evidence to show that it existed in Britain before, during and after the glacial period.
The most interesting feature of the glacial epoch is the extinct Lake Agassiz, which the receding ice of the later glacial period left in the Red River Valley of Minnesota,.
Cambrian rocks occur in each of these districts, and they are best developed in the South Australian high= lands, where they include a long belt of contemporary glacial deposits.
Mogilev is built up of Devonian deposits in the north, of Cretaceous in the east, and of Tertiary elsewhere, but generally is covered with a thick layer of Glacial and later alluvial deposits.
Haitinger, Monats., 1882, 3, p. 228); and by boiling succinic dialdehyde with ammonia and glacial acetic acid (C. Harries, Ber., 1901, 34, p. 1 497).
By dissolving red lead, Pb304, in glacial acetic acid and crystallizing the filtrate, colourless monoclinic prisms of lead tetracetate, Pb(C2H302)4, are obtained.
Of these Darkot, with a glacial staircase on each side, is typical.
Glacial detritus naturally plays a great part in the deposits on the polar continental shelves.
This confirms the theory of Christ that Europe was restocked mainly from Asia after the close of the glacial epoch, the south being closed to it.
It has a characteristic smell, and a biting taste; it is poisonous, and acts as a powerful antiseptic. It dissolves in water, 15 parts of water dissolving about one part of phenol at 16-17° C., but it is miscible in all proportions at about 70° C.; it is volatile in steam, and is readily soluble in alcohol, ether, benzene, carbon bisulphide, chloroform and glacial acetic acid.
The surface drifts of the greater part of the state, which are almost wholly of glacial origin, have provided Minnesota with a remarkably fertile soil.
Oxidizing agents convert anthracene into anthraquinone; the production of this substance by oxidizing anthracene in glacial acetic acid solution, with chromic acid, is the usual method employed for the estimation of anthracene.
Ecca Glacial Series (Dwyka Conglomerate).
In some of the larger valleys there are glacial terraces.
At the close of the glacial epoch the north Asiatic flora spread westwards into Europe and intermingled with the surviving vegetation.
There are large deposits of glacial and residual clays and clay shales throughout the state.
Much of the Triassic area is covered superficially by glacial drift and alluvium of the Trent.
At the close of the glacial period the alpine floras retreated to the mountains accompanied by an arctic contingent, though doubtless many species of the latter, such as Salix polaris, failed to establish themselves.
The last glacial reached its maximum at about 22,000 yr BP.
Unmistakable traces show that, while during the Glacial period Russia had an arctic flora and fauna, the climate of the Lacustrine period was more genial than it is now, and a dense human population at that time peopled the shores of the numberless lakes.
It crystallizes in colourless plates, possessing a violet fluorescence, melting at 112-113Ã‚° and boiling at 293-295Ã‚° C. By oxidation with chromic acid in glacial acetic acid solution, it is converted into diphenylene ketone (C8H4)2 CO; whilst on heating with hydriodic acid and phosphorus to 250-260Ã‚° C. it gives a hydro derivative of composition C13H22.
The Glossopteris flora of Australia occurs in certain regions in association with deposits which are now recognized as true boulderbeds, formed during widespread glacial conditions.
In the valleys of rivers which have overflowed their banks and on level bench lands there is considerable silt and vegetable loam mixed with glacial clay; but on the hills and ridges of western Washington the soil is almost wholly a glacial deposit consisting principally of clay but usually containing some sand and gravel.
slope of the Cascades and on the Okanogan Highlands glacial deposits of clay, gravel or sand, as well as vegetable loam, are mixed with the volcanic substances.
In 1871 he explored the glacial deposits of Finland and Sweden for the Russian Geographical Society, and while engaged in this work was offered the secretaryship of that society.
It may be condensed to a liquid, which boils at 8° C. It is readily soluble in benzene, glacial acetic acid, and in many hydrocarbons.
deep. The district affords frequent evidence of ice activity in the glacial period.
It is true that a great variety of evidence is afforded by the composition of the rocks, that glaciers have left their traces in glacial scratchings and transported boulders, also that proofs of arid or semiarid conditions are found in the reddish colour of rocks in certain portions of the Palaeozoic, Trias and Eocene; but fossils afford the most precise and conclusive evidence as to the past history of climate, because of the fact that adaptations to temperature have remained constant for millions of years.
The lakes and ponds, numbering several hundred, were formed by glacial action and the scenery of many of them is scarcely less attractive than that of the mountains.
Some of the stiff boulder clays or " till " so prevalent over parts of the north of England appear to have been deposited from ice sheets during the glacial period.
In places where the low ground is marshy, roads and railways often follow the ridge-lines of hills, or, as in Finland, the old glacial eskers, which run parallel to the shore.
During the first part of the Glacial period Russia seems to have been covered by an immense ice-sheet, which extended also over central Germany, and of which the E.
The former presents an intimate mixture of boulders brought from Finland and Olonets (with an addition of local boulders) with small gravel, coarse sand and the finest glacial mud, - the whole bearing no trace of ever having been washed up and sorted by water in motion, except in subordinate layers of glacial sand and gravel; the size of the boulders decreases on the whole from N.
The general characteristics of the lakes in the north differ from those of the south, the former being generally deep, with ragged rocky shores formed by glacial scouring which caused rock basins, the latter being mostly shallow.
from its source), and the Nyang Chu (the river of Shigatse and Gyantse), are both also of glacial origin.
There are four kinds of soil in Northern Europe: glacial till, alluvial, loess and geest.
all along Cape Cod; eskers, kames and river terraces afford the plainest evidences of the extent of the glacial sheet.
Since 1880 organized institutions of anthropology have taken the spade out of the hands of individual explorers in order to know the truth concerning Glacial or Pleistocene man.
The whole is overlaid with glacial deposits, sometimes 400 ft.
Glacial furrows, striae and elongated troughs are met with everywhere, running mostly from north-west to south-east, as well as asar or eskers, which have the same direction.
It forms a colourless vitreous mass, hence its name " glacial phosphoric acid."
Long Island, though modified by extensive glacial deposits, may be considered a N.E.
As the ice receded, it halted at various points, forming moraines and other glacial deposits.
Thus the soil of almost the entire state has been derived by glacial action.
There are thousands of lakes and ponds in the state, most of them very small and all, even including Lakes Erie and Ontario, the result of glacial action.
The soil is mostly glacial drift, but its depth and composition often vary greatly even within small areas.
half of the state, is mainly a clay which was formed by the glacial pulverizing of limestone and shale and is still forming from the decomposition of fragments of these substances.
The Pleistocene system in the South Island includes glacial deposits, which prove a great extension of the New Zealand glaciers, especially along the western coast.
The Grand Coulee represents the course of the Columbia river during the glacial period, when its regular channel was blocked with ice.
slope of the Olympics and Coast range is drained by several other small rivers into the Pacific. On the Cascade Mountains, at the heads of streams, are a number of lakes of glacial origin, the largest of which is Lake Chelan on the E.
The soils of western Washington are chiefly glacial, those of eastern Washington chiefly volcanic. In the low tidewater district of the Puget Sound Basin an exceptionally productive soil has been made by the mixture of river silt and sea sand.
Like the Lewis and Clark range, its crest is broken by numerous U-shaped wind-gaps and its west slope is cut by glacial troughs containing long narrow lake basins.
Small lakes and waterfalls, the result of glacial action, are numerous in the mountains.
West of the Missouri river the sheet of glacial drift is absent, and the lands everywhere show evidence of extensive stream erosion.
The glacial drift east of the Missouri river, unlike that of the New England states, is remarkably free from boulders and gravel, except in a few morainic belts.
The prairies in this second table-land are gently rolling, and are covered with drift from the continental ice-sheet of the glacial period.
East of the Missouri river this region is covered with glacial drift, and is noticeably different from the more level lands of the lower plains.
of this stream is almost free from glacial deposits and presents a strong contrast to the rest of the state.
The morainic belts and other obstructions in the drift plains hem in the waters in the intervening basins and create what are called " glacial lakes," var y ing in diameter from a few yards to several miles.
of the valley consist of glacial drift, and are well suited to the growing of grain.
Glacial gravels are well seen near Antrim town, and as drumlins between Ballymena and Ballycastle.
The surface is the typical glacial topography, with a few low, rocky hills, less than loo ft.
Fertile soil in New Hampshire is confined largely to the bottom-lands of the Merrimac and Connecticut rivers, where on deposits of glacial drift, which are generally quite deep in the southern half of the state, there is considerable alluvium.
It is presumed that in the Glacial epoch the genus was exterminated except in the areas in western North America where it still persists.
Anhydrous acetic acid - glacial acetic acid - is a leafy crystalline mass melting at 16.7° C., and possessing an exceedingly pungent smell.
==Pharmacology and Therapeutics== Glacial acetic acid is occasionally used as a caustic for corns.
Glacial action complicated the work of the latest cycle in the northern part of the system.
The basins have been variously ascribed to glacial erosion, to obstruction of normal outlet valleys by barriers of glacial drift, and to crustal warping in connection with or independent of the presence of the glacial sheet.
The prairies are, in brief, a contribution of the glacial period; they consist for the most part of glacial drift, deposited unconformably on an underlying rock surface of moderate or small relief.
The morainic belts are arranged in groups of concentric loops, convex southward, because the ice sheets advanced in lobes along the lowlands of the Great Lakes; neighboring morainic loops join each other in re-entrants (north-pointing cusps), where two adjacent glacial lobes came together and formed their moraines in largest volume.
The discovery of this significant looped arrangement of the morainic belts is the greatest advance in interpretation of glacial phenomena since the first suggestion of a glacial period; it is also the strongest proof that the ice here concerned was a continuous sheet of creeping land ice, and not a discontinuous series of floating icebergs, as had been supposed.
The moraines are of too small relief to be shown on any maps but those of the largest scale; yet small as they are, they are the chief relief of the prairie states, and, in association with the nearly imperceptible slopes of the till plains, they determine the course of many streams and rivers, which as a whole are consequent upon the surface form of the glacial deposits.
The complexity of the glacial period and its subdivision into several glacial epochs, separated by interglacial epochs of considerable length (certainly longer than the postglacial epoch) has a structural consequence in the superposition of successive till sheets, alternating with non-glacial deposits, and also a physiographic consequence in the very different amount of normal postglacial erosion suffered by the different parts of the glacial deposits.
When the ice of the last glacial epoch had retreated so far that Its front lay on a northward slope, belonging to the drainage area of the Great Lakes, bodies of water accumulated in front of the ice margin, forming glacio-marginal lakes.
The present site of Chicago was determined by an Indian portage or carry across the low divide between Lake Michigan and the headwaters of the Illinois river; and this divide lies on the floor of the former outlet channel of the glacial Lake Michigan.
Corresponding outlets are known for the glacial lakes Erie, Huron and Superior, and for a very large sheet of water, named Lake Agassiz, which once overspread a broad till plain in northern Minnesota and North Dakota.
The outlet of this glacial lake, called river Warren, eroded a large channel in which the Minnesota river, of to-day is an evident misfit.
Many additional features associated with the glacial period might be described, but space can be given to four only.
The best explanation suggested for bess is that, during certain phases of the glacial period, it was carried as dust by the winds from the flood plains of aggrading rivers, and slowly deposited on the neighboring grass-covered plains.
South-western Wisconsin and parts of the adjacent states of Illinois, Iowa and Minnesota are known as the driftless area, because, although bordered by drift sheets and moraines, it is free from glacial deposits.
The reason for this exemption from glaciation is the converse of that for the southward convexity of the morainic loops; for while they mark the paths of greatest glacial advance along lowland troughs (lake basins), the driftless area is a district protected from ice invasion by reason of the obstruction which the highlands of northern Wisconsin and Michigan (part of the Superior oldland~ offered to glacial advance.
The course of the upper Mississippi river is largely consequent i upon glacial deposits.
Its sources are in the morainic lakes in northern Minnesota; Lake Itasca being only one of many glacial lakes which supply the headwater branches of the great river.
Hence even the father of waters, like so many other rivers in the Northern states, owes many of its features more or less directly to glacial action.
The treelessness of the prairies cannot be due to insufficient time for tree invasion since glacial evacuation; for forests cover the rocky uplands of Canada, which were occupied by ice for ages after the prairies were laid bare.
Nevertheless the mountains are of especial interest to the physiographer who wishes to make a comparative study of land forms as affected by normal and by glacial sculpture, in order to give due attention to process as well as to structure and stage in the analysis and description of mountain topography.
In this central region, however, it is only by way of exception that the cirques were so far enlarged by retrogressive glacial erosion as to sharpen the preglacial dome-like summits into acute peaks; and in no case did glacial action here extend down to the plains at the eastern base of the mountains; but the widened, trough-like glaciated valleys frequently descend to the level of the elevated intermont basins, where moraines were deployed forward on the basin floor.
Lake Chelan, long and narrow, deep set between spurless ridges with hanging lateral valleys, and evidently of glacial origin, ornaments one of the eastern valleys.
The mountains in the southern part of the block, which had been reduced to subdued forms in the former cycle of erosion, were thus given a conspicuous height, forming the High Sierra, and greatly sharpened by revived erosion, normal and glacial.
Glacial erosion has been potent in excavating great cirques and small rock-basins, especially among the higher southern surmounting summits, many of which have been thus somewhat reduced in, height while gaining an Alpine sharpness of form; some of the short and steep canyons in the eastern slope have been converted into typical glacial troughs, and huge moraines have been laid on the desert floor below them.
in height, and the smaller Hetch-I-Ietchy Valley not far away, are regarded by some observers as owing their peculiar forms to glacial modifications of normal preglacial valleys.
In earlier literature the Lafayette formation was described under the name of Orange Sand, and was at one time thought to be the southern equivalent of the glacial drift.
This, however, is now known not to be the case, as remnants of the formation, isolated by erosion, lie under the old glacial drift in Illinois, and perhaps elsewhere.
The glacial ac drift covers something like half of the continent, though much less than half of the United States.
The number of glacial epochs now recognized is five, trot eounting minor episodes.
The glacial epochs which have been differentiated are the following, numbered in chronological order:
Essentially all phases of glacial and aqueo-glacial drift are represented.
The larger part of it seems to date from the closing stages of the Iowan epoch, but bess appears to have come into existence after other glacial epochs as well.
The estimate of the time between the first and last glacial epochs is based on changes which the earlier drift has undergone as compared with those which the younger drift has undergone.
Some of the estimates make the lapse of time since the first glacial epoch more than a million years, while others make it no more than one-third as long.
The nontO ~ glacial deposits are much like the Tertiary in kind and gaca.
Some of its several members are definitely correlated in time with some of the glacial epochs.
It is readily soluble in water, melts at 193° C., and is decomposed at a higher temperature into chromium sesquioxide and oxygen; it is a very powerful oxidizing agent, acting violently on alcohol, converting it into acetaldehyde, and in glacial acetic acid solution converting naphthalene and anthracene into the corresponding quinones.
" The term drift is now applied generally to the Quaternary deposits, which consist for the most part of gravel, sand, loam or brickearth and clay; it naturally refers to strata laid down at some distance from the rocks to whose destruction they are largely due; but, although applied to river deposits, the word drift is more appropriately used in reference to the accumulations of the Glacial period.
These narrow limits (called Wakhan) include the lofty spurs of the northern flank of the Hindu Kush, an impassable barrier at this point, where the glacial passes reach 19,000 ft.
It crystallizes in colourless plates, possessing a violet fluorescence, melting at 112-113° and boiling at 293-295° C. By oxidation with chromic acid in glacial acetic acid solution, it is converted into diphenylene ketone (C8H4)2 CO; whilst on heating with hydriodic acid and phosphorus to 250-260° C. it gives a hydro derivative of composition C13H22.
The contrast between the lower grounds of the Western and the Eastern Divisions is masked in many places by the general covering of the surface with glacial drift, which is usually a stiff clay composed on the whole of the detritus of the rocks upon which it rests, though containing fragments of rocks which have been transported from a considerable distance.
The same glacial beds of the Nicolas range send down tributary waters to the Panja or Wakhan river, below its junction with the ice stream from Wakhjir, and thus it becomes impossible to decide whether the glaciers of the Wakhjir or the glaciers of Nicolas should be regarded as effecting the most important contribution to the main stream.
In connexion with the objection based upon the sub-boreal character of the regions which were the cradle of the Aryans, as proved by the so-called palaeontology of the Aryan languages, it may be observed that by the end of the Glacial, and during the earlier Lacustrine (Post-Glacial) period, the vegetation of Turkestan and of Central Asia was quite different from what it is now.
The interior of the tableland consists for the most part of barren, grassless deserts, the surface being covered by gravel, loose fragments of rock, lava, driftsand, ashes and glacial detritus.
Similar glacial deposits occur also in South America, and members of the Glossopteris flora have been discovered in Brazil and elsewhere.
In South Africa, Glossopteris, Gangamopteris and other genera, identical with those from Australia and India, are abundantly represented, and here again, as in India and South America, the plants are found in association with extensive deposits of undoubted glacial origin.
Afghanistan, forming part of a thick series of marine beds known as the Salt Range group. This group of sediments in the extrapeninsular area of India includes a basal boulder-bed, referred on convincing evidence to the same geological horizon as the glacial deposits of the Indian peninsula (Talchir boulder-beds), South.
Some examples of this genus, described by Etheridge from Permo-Carboniferous beds in New South Wales, differ in some respects from the ordinary form, and bear a superficial resemblance to the Equise nected with a lowering of temperature and the prevalence of glacial conditions over a wide area in India and the southern hemisphere.
D., Calcutta, 1893); David, " Evidences of Glacial Action in Australia in Permo-Carboniferous time," Q.J.G.S., vol.
The latest Pliocene, or pre-Glacial, flora of northern Europe is best known from the Cromer Forest-bed of Norfolk and Suffolk, a fluvio-marine deposit which lies beneath the whole of the Glacial deposits of these counties, and passes downwards into the Crag, many of the animals actually associated with the plants being characteristic Pliocene species which seem immediately afterwards to have been exterminated by the increasing cold.
The incoming of the Glacial epoch does not appear to have been accompanied by any acclimatization of the plants - the species belonging to temperate Europe were locally exterminated, and Arctic forms took their places.
Space will not permit us to enter into any full discussion of the recurrence of Glacial and inter-Glacial periods and the influence they may have had on the flora.
The lakes which are found in all parts of the state and the rapids and waterfalls along the rivers are largely due to disturbances of the drainage lines by the ice invasion of the glacial period.
To the glacial action is also due the extensive removal of the original soil from the uplands, and the accumulation of morainic hills in many localities.
It crystallizes in plates (from alcohol) melting at 70-71° C. and boiling at 2 54°C. It is oxidized by chromic acid in glacial acetic acid solution to benzoic acid, dilute nitric acid and chromic acid mixture being without effect.
Many of them are derived from the glacial boulder-clays, or from the washing away of the finer materials contained in older clay formations.
Boulder-clay is a coarse unstratified deposit of fine clay, with more or less sand, and boulders of various sizes, the latter usually marked with glacial striations.
Well-drained soils occur on the sandy and gravely material but more waterlogged soils are found on river alluvium and glacial clays.
This recording has Pollard playing the bebop heavyweight against Scott's glacial diffidence.
Samson's putting stone - a glacial erratic boulder can be seen up on the hillside to the right.
This large glacial erratic bounder is slightly smaller and different in shape to the Gray Mare.
Active volcanoes and vast lava deserts stand in direct opposition to utterly boundless glacial landscapes.
Deep, well-drained fine loams and clays, over chalky till (glacial drift ).
From Camp 1 the route enters the western cwm which is a relatively flat glacial valley.
Their present morphology was shaped principally during the last glacial cycle (the Midlandian ), with subsequent modification throughout the post-glacial Holocene period.
This is a hole down through glacial debris which is very easily eroded.
Theory of glacial erosion, transport and deposition as a consequence of subglacial sediment deformation.
Maps, diagrams and photographs are used to describe the movement of the glacier and the glacial deposits.
dissected by valleys radiating from the peaks, which are largely attributed to glacial erosion.
The entire mountain is deeply dissected by valleys radiating from the peaks, which are largely attributed to glacial erosion.
Two glaciers converged across the North Shropshire Plain leaving thick layers of glacial drift.
The site of the station is comprised of a thick bed of alluvium of considerable depth which settled after the last glacial epoch.
Although there is no direct evidence of glacial erosion, the area would have been covered during the Ice Age.
In the lower lying alpine most of the caves have been scoured away or filled in with glacial erratics.
His doctors remain amazed at the glacial pace of his losses. Think taking estrogen will save your memory?
eutrophic lake of glacial origin in Northern Ireland.
It lacks the glacial pacing of the former and the visual flourishes of the latter, but at least displays a sense of humor.
The site contains links to other educational materials relating to glacial geology and geomorphology, and related links.
A research paper on the evolution of the glacial geomorphology has been published in Quaternary Science Reviews.
Sussex's field class to Nova Scotia examines aspects of its glacial history, sea-level change and coastal geomorphology.
glacial till deposits with granite boulders utilizing hand excavation from within a Greathead shield.
Icelandic glacial will be launching in the UK in August 2005 and will be distributed through premium retail outlets, hotels and restaurants.
glacial moraine which guarded the second area of marsh behind.
glacial geomorphology has been published in Quaternary Science Reviews.
glacial landforms left from the last ice age.
glacial erosion, the area would have been covered during the Ice Age.
glacial drift has covered up the useful walling stone.
The late glacial in Europe: pathways to complexity?
These include glacial, fluvial and a mixed group of periglacial deposits known as " Head "
Owing to the steepness of the valley sides of many glacial troughs, talus is commonly found in formerly glaciated mountain regions.
Natural soils have developed from a parent material consisting of glacial till derived from granite and granite gneiss.
The pit also has glacial gravels at the top from the Pleistocene.
We will try to locate a small winter snow pack and gage its melt rate in relation to glacial ice.
The till is thought to have been deposited from sea ice pushed up against the coast during an early glacial event.
Broadleaved woodland is limited to small patches alongside steeply incised streams and abandoned meander scars cut in the glacial deposits alongside the Glenelly river.
interglacial followed by the OIS 12 glacial.
Despite much research, the mechanism by which carbon dioxide levels were reduced during cold glacial periods relative to warm interglacials eludes us.
karst surface topography has been obscured by thick layers of glacial till.
At the end of the glacier is the massive Cho Rolpa glacial lake.
landforms created in glacial conditions.
We walked up to Easedale Tarn to look at glacial landforms left from the last ice age.
The rock here is magnesian limestone, which is covered by glacial deposits.
Well-defined mega-scale glacial lineations are present within the trough, produced by a palaeo-ice stream draining the Greenland Ice Sheet across the continental shelf.
It's quite lush at this level but higher up the scenery becomes drab with a number of glacial moraines.
However, in the Himalaya upwards of 80% of flow in the major longitudinal rivers is glacial meltwater.
Esker A ridge of sediment (often winding) made up of sand and gravel deposited by glacial meltwater.
Sea Rush near the pile of glacial moraine which guarded the second area of marsh behind.
Glacial retreat moraines are in evidence at Gunnerside Bridge, Lower Whita Bridge, below Grinton Bridge and by Ellerton Abbey.
Nepal flood Moving images of a glacial lake outburst flood in Nepal.
The sands and gravels of the alluvial plain originated as glacial outwash from the melting glaciers inland.
overburden of soil, debris or weaker rock was scoured away by glacial activity leaving a smooth rock surface.
permafrost conditions prevailed during glacial periods.
Has funicular access to a glacial bowl with wide open cruising pistes.
pollute are plans to dam all the major glacial rivers of Iceland to generate power for highly polluting heavy industry.
prow of the first ridge of Glacial Gravel south of the London Clay bowl.
ravine carved by glacial meltwater.
A glacial recession has occurred during the 20 th century.
refugiumresentation: ' Locating long-term glacial refugia in the Mediterranean Basin.
Pollan is a fish unique in Western Europe being a glacial relict from the last ice age.
ridges of glacial moraine toward the outer margins of the vale.
In fact, millions of people living in Asia and South America rely on glacial runoff for drinking water and irrigation.
Publications Hogan, K.A. (2001) glacial sedimentation and deglacial history of inner Disko Bugt, West Greenland.
The remainder of the week was spent with Prof. Ed Derbyshire, looking at various aspects of glacial sedimentology.
From the top of Baildon Moor we had a fine panorama of the surrounding district, including four parallel glacial spillways to the west.
St Peter's School, Hereford A study of the development of archeological stratigraphy within natural, glacial strata in central Hereford.
The effect of Quinag on ice flow can be checked by measuring glacial striae on the quartzites.
Topsoil stripping revealed a similar surface to that on Area 1. At the southern end there was an orange brown subsoil overlying glacial gravel.
Much of the karst surface topography has been obscured by thick layers of glacial till.
Landscape Key Characteristics Broad flat glacial trough between the hills of west Fermanagh.
However, during these glacial periods it is likely that much of the County resembled the tundra of today's arctic provinces.
The repetition of the same species in the arctic regions and in the high mountains of the North Temperate region is generally attributed to the exchange which took place during the glacial period.
The Antarctic-Alpine region is the complement of the ArcticAlpine, but unlike the latter, its scattered distribution over numerous isolated points of land, remote from great continental areas, from which, during migrations like those attending the glacial period in the northern hemisphere, it could have been recruited, at once accounts for its limited number of species and their contracted range in the world.
It has a characteristic smell, and a biting taste; it is poisonous, and acts as a powerful antiseptic. It dissolves in water, 15 parts of water dissolving about one part of phenol at 16-17Ã‚° C., but it is miscible in all proportions at about 70Ã‚° C.; it is volatile in steam, and is readily soluble in alcohol, ether, benzene, carbon bisulphide, chloroform and glacial acetic acid.
Soc. Chem., 1882 , 37, P. 434; 38, p. 60) have also shown that the specific heat of the gas decreases with increase of temperature until it reaches a minimum at about 198-253Ã‚° C. Cryoscopic determinations of the molecular weight of nitrogen peroxide dissolved in glacial acetic acid show that it corresponds to the molecular formula N204 at low temperatures (W.
The lake really lies on the watershed between the two, and is probably a glacial relic. Its contribution to either infant stream appears to depend on conditions of overflow determined by the blocking of ice masses towards one end.
It crystallizes in large plates, which melt at 98.5Ã‚° C. and boil at 390Ã‚° C. It is readily soluble in warm ether and in hot glacial acetic acid.
Here the tributary streams tumble down the sides of the lake valleys, whose bottoms have been deepened by glacial erosion, leaving the tributary valleys hanging.
It may be condensed to a liquid, which boils at 8Ã‚° C. It is readily soluble in benzene, glacial acetic acid, and in many hydrocarbons.
Chem., 1889, 3, p. 11.) Iodine monochloride in glacial acetic acid solution was used by A.
Anhydrous acetic acid - glacial acetic acid - is a leafy crystalline mass melting at 16.7Ã‚° C., and possessing an exceedingly pungent smell.
But the Hudson is strikingly exceptional in this respect; it possesses a deep and navigable tide-water channel all through its gorge in the highlands, a feature which has usually been explained as the result of depression of the land, but may also be explained by glacial erosion without change of land-level; a feature which, in connection with the Mohawk Valley, has been absolutely determinative of the metropolitan rank reached by New York City at the Hudson mouth.
It is readily soluble in water, melts at 193Ã‚° C., and is decomposed at a higher temperature into chromium sesquioxide and oxygen; it is a very powerful oxidizing agent, acting violently on alcohol, converting it into acetaldehyde, and in glacial acetic acid solution converting naphthalene and anthracene into the corresponding quinones.
Physiography is well described in The Illinois Glacial Lobe (U.S. Geological Survey, Monograph, xxxviii.) and The Water Resources of Illinois (U.S. Geological Survey, Annual Report, xviii.).
On solution in glacial acetic acid and addition of nitric acid, Ã¯¿½nitroalizarin OH //CO /Ã¯¿½H (alizarin orange) I I OH /CO I / IOH CO //OH Various industries are carried on in Leblanc alkali works, as follows: I.
Glacial action may be studied well as far south as 36Ã‚°.
with zinc chloride and glacial acetic acid at 145Ã‚° C. it yields resacetophenone (HO) 2 C 6 H 3 Coch 3 (M.
The loess, the re-sorted residual clays, and the glacial clays are all used for the production of brick.
A second hydrate, H 2 SO 4, H 2 0, may be obtained as rhombic crystals, which melt at 7Ã‚° and boil at 205 Ã‚°, by diluting the strong acid until it has a specific gravity of 1.78, and cooling the mixture; this compound is sometimes known as glacial sulphuric acid.
The south coast is flat next the sea; but immediately underneath Vatnajokull there is a strip of gravel and sand, brought down and deposited by the glacial streams. The largest low-lying plain of Iceland, lying between Myrdalsjokull and Reykjanes, has an area of about 1550 sq.
The eastern part of the state is covered with a thick mantle of Quaternary (Pleistocene), and the greatest part of the western portion with very thick deposits of Miocene and Pliocene (Tertiary) To the Pleistocene belong the alluvium, loess and glacial drift, and in part the sand-hills.
The glacial geology, with a summary of the literature thereon, is described by the same writer in the Quarterly Journal of the Geological Society, 1904, vol.
It crystallizes in plates (from alcohol) melting at 70-71Ã‚° C. and boiling at 2 54Ã‚°C. It is oxidized by chromic acid in glacial acetic acid solution to benzoic acid, dilute nitric acid and chromic acid mixture being without effect.
The Gap is a ravine carved by glacial meltwater.
Oral presentation: ' Locating long-term glacial refugia in the Mediterranean Basin.
Sand and gravel quarries are a significant pressure in areas with ridges of glacial moraine toward the outer margins of the vale.
Publications Hogan, K.A. (2001) Glacial sedimentation and deglacial history of inner Disko Bugt, West Greenland.
St Peter 's School, Hereford A study of the development of archeological stratigraphy within natural, glacial strata in central Hereford.
However, during these glacial periods it is likely that much of the County resembled the tundra of today 's arctic provinces.
At 600 mm the high percentage of birch, grass and herbs suggests a cold late glacial climate probably with a tundra type vegetation.
Certainly both the artist 's crystalline, glacial brushwork and intense ultramarine skies recall the visionary realism of early Flemish painting.
Lilac Lynx - The body should be a glacial white color, and the points are pale frosty grey with a pinkish tone ticked with darker lilac tabby markings.
It winds along the shore of Lake Dubonnet and the headwaters of the Platte River and passes an ancient glacial lake.
There is never a dull moment on a Mississippi cruise, as the waterway passes through swamps, glacial lakes, rapids and dams.
Natural bogs developed from glacial melting, over ten thousand years ago.
Follow basic rules with wine temperatures for reds slightly cooler than room temperature and whites chilled but not to glacial temperatures.
"The campground we are staying at is smack dab in the middle of a natural rock formation from glacial movements millions of years ago.
This mask features a formula with glacial clay to draw out impurities and excess oils to refine pores for exceptional clarity and a revitalized appearance.
The most definite are connected with estimates of the time since the last glacial epoch, and are calculated from the amount and rate of recession of certain falls, notably those of the Niagara and Mississippi (St Anthony Falls) rivers.
An extensive area of glacial deposits 50 shows that a sheet of ice formerly covered the whole eastern slope to a great distance from the mountains.
The time since the last glacial epoch is but a fraction of the time since the first probably no more than a fifteenth or a twentieth.
In the west the Quaternary deposits are not, in all cases, sharply separated from the late Tertiary, but the deposits of glacial drift, referable to two or more glacial epochs, are readily differentiated from the Tertiary; so, also, are certain lacustrine deposits, such as those of the extinct lakes Bonneville and Lahontan.
So also have the shorelines of the Great Lakes, which came into existence at the close of the glacial period.
Much has been written and more said concerning the existence of man in the United States before the last glacial epoch.
The present state of evidence, however, seems to afford no warrant for the conclusion that man existed in the United States before the end of the glacial period.
While these ancient events shaped the topography in a broad way, its final development was comparatively recent, during the glacial period, when the loose materials were scoured from some regions and spread out as boulder clay, or piled up as moraines in others; and the original water-ways were blocked in many places.
The uneven carving down of the older mountain systems, especially that of the Archean protaxis, and the disorderly scattering of glacial material provide most of the lake basins so characteristic of Canada.
The very flat and rich prairie near Winnipeg is the former bed of the glacial Lake Agassiz; but most of the prairie to the west is of a gently rolling character and there are two rather abrupt breaks in the plain, the most westerly one receiving the name of the Missouri Coteau.
The rolled crystals of sapphire occur, with garnet and other minerals, in glacial deposits, and have probably been derived from dykes of igneous rocks, like andesite and lamprophyre.
Mitscherlich in 1834, may be prepared by reducing nitrobenzene in alcoholic solution with zinc dust and caustic soda; by the condensation of nitrosobenzene with aniline in hot glacial acetic acid solution; or by the oxidation of aniline with sodium hypobromite.
Clew Bay, with its islets capped by glacial drift, is a submerged part of a synclinal of Carboniferous strata, and Old Red Sandstone comes out on the north side of this, from near Achill to Lough Conn.
Jacobsen has also obtained benzaldehyde by heating benzal chloride with glacial acetic acid: C 6 H 5 CHC1 2 +CH 3 000H =CH30001 +HC1+C6H5CHO.
long, half a mile to a mile wide, and nearly a mile deep, eroded out of hard massive granite by glacial action.
The Romsdal and Naerodal of Norway and Lauterbrunnen of the Alps are well characterized glacial valleys of the Yosemite type, and in S.E.
deep, but west of the Allegheny river, where harder rocks have resisted such deep dissection and glacial drift has filled depressions or smoothed rough surfaces, the uplands are broader and the valleys wider and shallower.
The north-west and north-east sections contain some glacial drift but the soil in these parts is not suitable for cultivation except in the larger valleys in the north-west where it is drained by glacial gravel or there is some sandy loam mixed with clay.
There are still enormous glaciers about the head of the Brahmaputra, but the glacial epoch of the Chang-t'ang highlands has passed away, though comparatively recently.
At Archbald is a large glacial "pot hole," about 20 ft.
The climate of the glacial region has often been compared to that of the polar regions, but they are widely different.
As for the explanation of the community between the alpine and arctic floras, all authorities are agreed that the key to the problem is furnished by the occurrence of the glacial period.
The greater richness of certain districts in the matter of species is partly due to the variety of soils encountered therein; but in part may be explained by the fact that these districts were the first to be freed from the ice-sheet at the end of the glacial period.
The former connexion between the Arctic and the Alps, which has left such unmistakable traces in the present alpine flora, affords, as regards the fauna also, the only possible explanation of the present geographical distribution of many alpine forms; but it is chiefly among the Invertebrata that we find this collateral testimony to the influence of the glacial period.
Its specific gravity is 96, a little less than that of water, and it dissolves freely in alcohol, ether and glacial acetic acid.
In spite of the bulk of the evidence being in favour of geniality of climate, it is necessary to observe that certain deposits have been recognized as glacial; in the culm of the Frankenwald, in the coal basins of central France, and in central England, certain conglomeratic beds have been assigned, somewhat doubtfully, to this origin.
Glacial deposits certainly do exist in the Permo-carboniferous formations, which are described under that head, but in the true Carboniferous system glaciation may be taken as not proven.
The appearance of northern shells in the upper divisions of the Pliocene series indicates the approach of the Glacial period, and glacial drift containing Scandinavian boulders now covers much of the country east of the Zuider Zee.
The earliest eruptions of Etna are older than the Glacial period in Central and Northern Europe.
Considerable interest attaches to the diamonds found in Wisconsin, Michigan and Ohio near the Great Lakes, for they are here found in the terminal moraines of the great glacial sheet which is supposed to have spread southwards from the region of Hudson Bay; several of the drift minerals of the diamantiferous region of Indiana have been identified as probably of Canadian origin; no diamonds have however yet been found in the intervening country of Ontario.
" The occurrence of stones and boulders far removed from their parent source early attracted the attention of geologists, but for a long period the phenomena, now known as of glacial origin, were unexplained, and the drifts were looked upon as little more than ` extraneous rubbish,' the product of geological agents, quite distinct from those which helped to form the more ` solid ' rocks that underlie them."
In writing and in conversation the geological expression " drift " is now usually understood to mean Glacial drift, including boulder clay and all the varieties of sand, gravel and clay deposits formed by the agency of ice sheets, glaciers and icebergs.
See GLACIAL PERIOD; PLEISTOCENE; BOULDER CLAY.
Chromic acid in glacial acetic acid solution oxidizes it to picene-quinone, picene-quinone carboxylic acid, and finally to phthalic acid.
These are in part of glacial origin, and contain Scandinavian boulders; but fluviatile and aeolian deposits also occur.
Covering the higher parts of the south-western Palaeozoic area in most places are rolling hills of boulder clay or stony moraines; while the lower levels are plains gently sloping toward the nearest of the Great Lakes and sheeted with silt deposited in more ancient lakes when the St Lawrence outlet was blocked with ice at the end of the glacial period.
The old shore cliffs and gravel bars of these glacial lakes are still well-marked topographical features, and provide favourite sites for towns and cities.
He was the author of many scientific papers and reports, especially on the surface geology and glacial phenomena of the northern and western parts of Canada.
The former, as is well known, owes its origin to the action of ice on the mountains of Norway in the Glacial period.
Some parts of Denmark are supposed to have been finally raised out of the sea towards the close of the Cretaceous period; but as a whole the country did not appear above the water till about the close of the Glacial period.
Or the stream by cutting into another stream (piracy), but cutting through a barrier near its head waters, by entering a region of looser or softer rock; and by glacial drainage, may form a flood plain simply by filling up its valley (alluviation only).
The Dombes is characterized by an impervious surface consisting of boulder clay and other relics of glacial action.
Glacial deposits spread over the lower grounds and striae occur at great heights on the Black Mountains.
The Lakes of the Plains lie in hollows of the glacial detritus which is strewn so thickly over the lower grounds.
On the east side of Scotland, where so many fragments of the Secondary rocks occur as boulders in the glacial deposits, a large mass of strata was formerly exposed at Linksfield to the north of Elgin, containing fossils which appear to show it to belong to the Rhaetic beds at the top of the Trias.
Enormous numbers of flints and also less abundant fragments of chalk are found in glacial deposits bordering the Moray Firth.
Under the Post-Tertiary division come the records of the Ice Age, when Scotland was buried under sheets of ice which ground down, striated and polished the harder rocks over the whole country, and left behind them the widespread accumulation of clay, gravel and sand known as Glacial Deposits.
On the north the principal glacial tributary of Lake Victoria forms, within the folds of the gigantic spurs of the Nicolas mountains, a series of smaller lakes, or lakelets, before joining the great lake itself.
Neither Lake Victoria nor Lake Chakmaktin derives any very large contributions from glacial sources other than those of the Nicolas range.
The glacial origin of the Pamir valleys is everywhere apparent in their terrace formations and the erratic blocks and boulders that lie scattered about their surface.
Although the superficial area of glacial ice from which the Ab-iWakhjir derives the greater part of its volume is not equal to that found on the Nicolas range, it is quite impossible to frame any estimate of comparative depth or bulk, or to separate the volume of its contributions at any time from those which, combined, derive their origin from the Nicolas range.
If the Aksu (or Murghab) and the Pamir river from Lake Victoria are to be considered in the light of independent tributaries, it is probable that the Ab-i-Panja contributes as large a volume of glacial flood to the Oxus as either of them.
230 „ To the glacial sources of the Ab-i-Wakhjir, about.
It may be synthetically prepared by the fusion of cymol sulphonic acid with caustic potash; by the action of nitrous acid on 1-methyl-2-amino-4-propyl benzene; by prolonged heating of 5 parts of camphor with r part of iodine; or by heating carvol with glacial phosphoric acid.
On solution in glacial acetic acid and addition of nitric acid, ï¿½nitroalizarin OH //CO /ï¿½H (alizarin orange) I I OH /CO I / IOH CO //OH Various industries are carried on in Leblanc alkali works, as follows: I.
The great boulder bed terraces in some of the valleys of the northern slopes of the Ferozkhoi plateau are probably of glacial origin.
of Murfreesboro; this is the first place in North America where diamonds have been found in situ, and not in glacial deposit or in river gravel.
Much of the ruggedness and beauty of the mountains is due to the erosive action of many alpine glaciers that once existed on the higher summits, and which have left behind their evidences in valleys and amphitheatres with towering walls, polished rock-expanses, glacial lakes and meadows and tumbling waterfalls.
Glacial action may be studied well as far south as 36°.
All of the Sierra lakes and ponds are of glacial origin and there are some thousands of them.
The lower lake line is about 8000 ft.; it is lower to the north than to the south, owing to the different climate, and the different period of glacial retrogression.
It is estimated by John Muir that on an average " perhaps more than a mile " of degradation took place in the last glacial period; but with regard to the whole subject of glacial action in California as in other fields, there is considerable difference of opinion.
Volcanic action has likewise left abundant traces, especially in the northern half of the range, whereas the evidences of glacial action are most perfect (though not most abundant) in the south.
All these lakes, and the other mountain lakes before referred to, show by the terraces about them that the water stood during the glacial period much higher than it does now.
Various other things indicate a separation of the islands from the mainland in quaternary times; since which, owing to the later southward movement on the continent of northern forms in glacial times, there has been a struggle for existence on the mainland from which the islands have largely escaped.
Local glaciation has modified the higher levels of the Bighorn Mountains, giving glacial cirques, alpine peaks and many mountain lakes and waterfalls.
Mathes, " Glacial Sculpture of Bighorn Mountains, Wyoming," pp. 167-190 of Pt.
in the manner that is typical of glacial action.
The red rocks may in some cases suggest desert conditions; and there is good reason to suppose that in what are now Norway and China a glacial cold prevailed early in the period.
At some period, long subsequent to its original excavation, and after many large stalactites had grown, it was completely filled with glacial mud charged with acid, whereby the dripstone was eroded into singularly grotesque shapes.
Cirques, valley troughs, numberless beautiful cascades, sharpened alpine peaks and ridges, glacial lakes, and valley moraines offer everywhere abundant evidence of glacial action, which has modified profoundly practically all the ranges.
The whole of Finland is covered with Glacial and post-Glacial deposits.
The former of these, representing the bottommoraine of the ice-sheet, are covered with Glacial and post-Glacial clays (partly of lacustrine and partly of marine origin) only in the peripheral coast-region - or in separate areas in the interior depressions.
Some Finnish geologists - Sederholm for one - consider it probable that during the Glacial period an Arctic sea (Yoldia sea) covered all southern Finland and also Scania (Sickle) in Sweden, thus connecting the Atlantic Ocean with the Baltic and the White Sea by a broad channel; but no fossils from that sea have been found anywhere in Finland.
It was entirely covered with the bottom moraine of the great ice-sheet of the Glacial Epoch, resting upon Silurian sandstones and limestones.
In places sands and clays overlie the glacial deposits.
The most recent deposits of Sweden date from the Glacial and Post-Glacial periods.
At the beginning of the Glacial period the height of Scandinavia above the level of the sea was greater than at present, Sweden being then connected with Denmark and Germany and also across the middle of the Baltic with Russia.
These deposits, known as glacial sand and glacial clay, cover most parts of Sweden south of the provinces of Kopparberg and Vermland, the more elevated portions of the provinces of Elfsborg and Kronoberg excepted.
In the glacial clay shells of Yoldia arctica have been met with in many places (e.g.
The glacial clay consists generally of alternate darker and lighter coloured layers, which give it a striped appearance, for which reason it has often been called hvarfvig lera (striped clay).
The glacial clay of the Silurian regions is generally rich in lime and is thus a marl of great fertility.
The deposits of glacial sand and clay are found in the southern part of Sweden at a height ranging from 70 to 550 ft.
On the coasts of the ancient ice-sea, in which the glacial clay was deposited, there were heaped-up masses of shells which belong to species still extant around Spitzbergen and Greenland.
Of wild flowering plants only a very few are endemic species (though more are endemic varieties); the bulk are immigrants after the last glacial epoch.
During the Glacial period its glaciers were much larger than at present, whilst during a later portion of the Quaternary period (to judge by the marine fossils found as high as 300 ft.
The fluorene is separated from this by placing it in a freezing mixture, and is then redistilled or crystallized from glacial acetic acid, or purified by means of its picrate.
with zinc chloride and glacial acetic acid at 145° C. it yields resacetophenone (HO) 2 C 6 H 3 Coch 3 (M.
Scattered among the mountains are numerous (glacial) lakes.
Crossing the lower peninsula from Saginaw Bay west by south through the valleys of the Saginaw, Maple and Grand rivers, is a depression - the former channel of an old glacial river - in which elevations for a considerable area are less than loo ft.
Several thousand lakes of clear water, formed by glacial action, dot the surface of the state, and many of them are lined with picturesque woodland shores.
Next 5 cc. of glacial acetic acid are added, the solution cooled, and 5 cc. of a solution of potassium iodide (300 grammes to the litre) and the standard solution of sodium thiosulphate run in from a burette until the brown colour has nearly disappeared.
A few drops of starch solution are then added, and when the blue colour has nearly vanished a drop or two of methyl orange makes the end reaction very sharp. The thiosulphate solution is standardized by dissolving o 3 to o 5 gramme of pure copper in 3 cc. of nitric acid, adding 50 cc. of water and 5 cc. of ammonia, and titrating as above after the addition of 5 cc. of glacial acetic acid and 5 cc. of the potassium iodide solution.
After his return to England in 1862 Wallace visited the continent, especially Switzerland, for rest and change (1866, 1896) and the study of botany and glacial phenomena (August 1895).
The great terminal moraine of the glacial epoch crosses the N.E.
In the northern and north central parts of the state, where the soil consists partly of glacial drift, the species have a wider range than is the case farther S., where the soil is more uniform.
Those of the northern and central sections are made up in part of glacial drift; those of the S.
13,650 Geologically, perhaps, the most interesting rocks in the Carboniferous are the glacial conglomerates, containing ice-scratched, erratic blocks.
The northern limit of the glacial beds is in dispute; they have been described as far north as Ashford.
There are, besides, numerous mountain tarns of small size, most of them in hollows barred by the glacial drift which covers a great part of the district.
The last well-marked lowering of the land took place in the Pleistocene period, when it was accompanied by glacial conditions, through which the greater part of northern England and the Midlands was covered by ice; a state of things which led directly and indirectly to the deposition of those extensive boulder clays, sands and gravels which obscure so much of the older surface of the country in all but the southern counties.
above the sea, with luxuriantly wooded tops and bald, sheer sides scarred with marks of glacial action; the beachless coast is only a narrow ledge between the mountains and the sea, and unlike the coast of Norway, to which in outline it is not dissimilar, is bold, steep and craggy.
Everywhere the evidences of glacial action abound.
The Copper, the Susitna and its tributary, the Yentna, as well as the Skwentna, a tributary of the Yentna from the west, all run through picturesque canyons, and their upper courses are characterized by glacial and torrential feeders.
behind a fringing foreland of glacial debris.
The glacier or ice sheet overran all Maine, irregularly scouring out the bed rock to produce rock basins, damming up many river valleys with glacial deposits and completely disarranging the drainage lines.
The glaciation is also responsible for the poor soil of most of the state, for, although the rocks are the same crystallines which give good soils further south in unglaciated regions, all the decayed portions of the Maine rocks have been removed by glacial erosion, revealing fresh, barren rock over great areas, or depositing the rather sterile hard-pan as a thin coating in other places.
occurred during the glacial period, perhaps toward its close, and is responsible for the second most important feature of Maine physiography, the embayed coast.
The soil is for the most part glacial drift, containing a large mixture of clay with sand or gravel, and the sub-soil is mostly " hard-pan," i.e.
mingled clay and boulders which have been so much compressed by glacial action as to make the mixture hard and ledge-like.
Stone, The Glacial Gravels of Maine and their Associated Deposits (Washington, 1899); T.
vii.) that the high-level valleys of glacial formation which distinguish the Pamirs have no real counterpart in the Chang or plains of Tibet.
The Wakhan glaciers under the Wakhjir water-parting, Lake Chakmaktin near the sources of the Aksu, and Lake Victoria of the Great Pamir have all been claimed as indicating the Glacial of true source of the Oxus.
their hydrographical conditions proves that neither of the the two lakes, Victoria (13,400 ft.) or Chakmaktin (13,020 ft.), can justly be regarded as sources, both of them being derived from the same mighty system of glacial snowfields on the summit of the Nicolas range.
Both may be regarded as incidents in the course of glacial streams (incidents which are diminishing in volume day by day), ' rather than original springs or sources.
There is evidence also that glacial moraine formations from time to time may have largely affected the catchment area of these tributary streams. It would be as rash to assert that from Lake Victoria no waters could ever have issued with an eastward flow as it would be to state that 'from Chakmaktin none ever flow westwards.
The floor of the Basin Region is formed of alluvium washed from the high plateaus and mountain ranges, a part of which has accumulated in alluvial fans, and part in the greatly expanded lakes which existed here in the glacial period.
Lake Bonneville is the name given to the most important of the much greater lakes of the glacial period, whose old shore-lines are plainly visible on many mountain slopes.
Patches of glacial boulder clay and gravel lie upon the older rocks over most of the area.
Northern Missouri is covered with a mantle of glacial deposits, generally thick, although in the stream valleys of the north-east the bed-rocks are widely exposed.
The southern limit of these glacial deposits is practically the bluffs bordering the Missouri river, except for a narrow strip along the Mississippi below St Louis.
This variety is due to the presence of different forms of glacial drift, and to the variety of surface rocks.
It seems possible that n is not a large number, and if we take x equal, say, to 200, we come to the most recent estimate - the astronomical - of the date of the earth's glacial epoch, when the sun's radiation was certainly not much more than it is now, while this factor would differ materially from unity.
A bed of conglomerate is regarded as of glacial origin.
of surface soil, glacial drift and impermeable gault clay and thence passed for a further depth of 70 ft.
Nearly all clays, notably those from the Glacial deposits, naturally contain sand and stones, 40 to 50% by weight of which is not too much if uniformly distributed an y 1 if the clay is otherwise good.
This reservoir is situated in a true Glacial lake-basin, and having therefore all the appearance of a natural lake, is commonly known as Lake Vyrnwy.