Monazite, a phosphate of thorium and other rare earths, contains on the average about i cc. per gram.
The extraction (as is the case with all the rare earths) is a matter of great difficulty.
The movements of the shaft are controlled by relays and electro-magnets which operate in response to the action of the subscriber whose telephone is fitted with a 'calling mechanism which, when the subscriber calls, earths the line a certain number of times for each figure in the number of the wanted subscriber.
Our regions will not be natural unless they mark out real discontinuities both of origin and affinity, and these we can only seek to explain by reference to past changes in the earths history.
To quote further: Existing floras exhibit only one moment in the history of the earths vegetation.
The great primary divisions of the earths flora present themselves at a glance.
the later period of the Mesozoic era saw the almost sudden advent of a fully developed angiospermous vegetation which rapidly occupied the earths surface, and which it is not easy to link on with any that preceded it.
The alkaline earths were assumed to be elements until 1807, when Sir H.
Berzelius's investigation of the action of the electric current on salts clearly demonstrated the invaluable assistance that electrolysis could render to the isolator of elements; and the adoption of this method by Sir Humphry Davy for the analysis of the hydrates of the metals of the alkalis and alkaline earths, and the results which he thus achieved, established its potency.
These crude earths, yttria and ceria, have supplied most if not all of the " rare earth " metals.
In 1880 Marignac examined certain earths obtained from the mineral samarksite, which had already in 1878 received attention from Delafontaine and later from Lecoq de Boisbaudran.
Taking as a basis the nature of the source of compounds, he framed three classes: " mineral," comprising the metals, minerals, earths and stones; " vegetable," comprising plants, resins, gums, juices, &c.; and " animal," comprising animals, their different parts and excreta.
Rubidium, caesium, thallium, indium and gallium were first discovered by means of this instrument; the study of the rare earths is greatly facilitated, and the composition of the heavenly bodies alone determinable by it.
The views of Becher on the composition of substances mark little essential advance on those of the two preceding centuries, and the three elements or principles of salt, mercury and sulphur reappear as the vitrifiable, the mercurial and the combustible earths.
rend., 1904 seq.) by fractional crystallization of the nickel double nitrates, the ethyl sulphates, and the bismuth double nitrates of the terbium earths.
Such a summary of the salient facts in the, geographical distributio~ of plants sufficiently indicates the tangled fabric of the earths existing floral covering.
Under such circumstances the earths vegetation would be very different from what it is, and the study of plant distribution would be a simple affair.
It is true that the earths physical geography presents certain broad features to which plants are adapted.
lime) were found to be very similar in properties to those of the alkalis, they were called alkaline earths.
ERBIUM (symbol, Er; atomic weight, 165-166), one of the metals of the rare earths.
In 1883 he began an inquiry into the nature and constitution of the rare earths.
A later result of this method of investigation was the discovery of a new member of the rare earths, monium or victorium, the spectrum of which is characterized by an isolated group of lines, only to be detected photographically, high up in the ultra-violet; the existence of this body was announced in his presidential address to the British Association at Bristol in 1898.
Throughout his life he paid great attention to the "rare earths" and the problem of separating and distinguishing them; in 1878 he extracted ytterbia from what was supposed to be pure erbia, and two years later found gadolinia and samaria in the samarskite earths.
The metals of the alkalis and alkaline earths, also magnesium, burn in sulphur vapour as they do in oxygen.
These nitrates generally occur as efflorescences caused by the oxidation of nitrogenous matter in the presence of the alkalies and alkaline earths.
It includes chalky limestones, siliceous earths, red clay, and, at the top, a layer of mudstone composed mainly of volcanic dust.
In common with Gay Lussac and Davy, he held subterraneous thermic disturbances to be probably due to the contact of water with metals of the alkalis and alkaline earths.
Each has its atmospheres, waters and earths, but in the one they are natural and in the other spiritual.
Rare Earths >>
It is precipitated as the metal from solutions of its salts by the metals of the alkalis and alkaline earths, zinc, iron, copper, &c. In its chemical affinities it resembles arsenic and antimony; an important distinction is that it forms no hydrogen compound analogous to arsine and stibine.
In a smaller degree these alkaline properties are shared by the less soluble hydrates of the "metals of the alkaline earths," calcium, barium and strontium, and by thallium hydrate.
The monometallic salts of the alkalis and alkaline earths may be obtained in crystal form, but those of the heavy metals are only stable when in solution.
If the heating be with charcoal, the trimetallic salts of the alkalis and alkaline earths are unaltered, whilst the monoand di-salts give free phosphorus and a trimetallic salt.
In its chemical properties it closely resembles barium and strontium, and to some degree magnesium; these four elements comprise the so-called metals of the "alkaline earths."
The fluorides of the alkali metals, of silver, and of most of the heavy metals are soluble in water; those of the alkaline earths are insoluble.
earths, and the slag 64.6 and 2 7.45% of the same respectively.
The world is represented as an orderly structure of various heavens and various earths, which is borne and supported by the aeons, the angels of light.
These large divisions need physiographic subdivision, which will now be made, following the guide of structure, process and stage; that is, each subdivision or province will be defined as part of the earths crust in which some similarity of geological structure prevails, and upon which some process or processes of surface sculpture have worked long enough to reach a certain stage in the cycle of physiographic development.
The ranges are primarily the result of faulting and uplifting of large blocks of the earths crust.
Next, dependent on the inclination of the earths axis, is the division of the planetary year into the terrestrial seasons, with winter and summer changes of temperature, wind-strength and precipitation: these seasonal changes are not of the restrained measure that is characteristic of the oceanic southern temperate zone, but of the exaggerated measure appropriate to the continental interruptions of ~the northern land-and-water zone, to which the term temperate is so generally inapplicable.
In the ordinary laboratory the Bunsen flame has become universal, and a number of substances, such as the salts of the alkalis and alkaline earths, show characteristic spectra when suitably placed in it.
Dufour' discovered that the lines into which the band spectra of the fluorides of the alkaline earths may be resolved widen towards the red under increased pressure.
The spectra, for instance, of the oxides and haloid salts of the alkaline earths show great resemblance to each other, the bands being similar and similarly placed.
The oxide Eu 2 0 3 occurs in very small quantity in the minerals of the rare earths, and was first obtained in 1896 by E.
When lime is used as a matrix, certain natural earths such as pozzuolana or trass, or, failing these, powdered bricks or tiles, may be used instead of sand with great advantage.
It is not magnetic. It stands near the positive end of the list of elements arranged in electromotive series, being exceeded only by the alkalis and metals of the alkaline earths; it therefore combines eagerly, under suitable conditions, with oxygen and chlorine.
After removing the uranium, it was found that the bismuth separated with a very active substance - polonium; this element was afterwards isolated by Marckwald, and proved to be identical with his radiotellurium; that the barium could be separated with another active substance - radium; whilst a third fraction, composed mainly of the rare earths (thorium, &c.), yielded to Debierne another radioactive element - actinium, which proved to be identical with the emanium of Giesel.
There is a mass of evidence to show that radium is to be regarded as an element, and in general its properties resemble those of the metals of the alkaline earths, more particularly barium.
LANTHANUM [[[symbol]] La, atomic weight 139.0 (0=16)] one of the metals of the cerium group of rare earths.
Earths and stones.
The earth-stopper "stops out" and "puts to" - the first expression signifying blocking, during the night, earths and drains to which foxes resort, the second performing the same duties in the morning so as to prevent the fox from getting to ground when he has been found.
CERIUM (symbol Ce, atomic weight 140.25), a metallic chemical element which occurs with the rare earths in the minerals cerite, samarskite, euxenite, monazite, parisite and many yttrium minerals.
an impure solution of common salt, especially removing the alkaline earths and so forth by addition of sodium or ammonium carbonate and settling out the precipitate formed.
Alkaline Earths >>
The separation of scandium from wolframite (which contains 0.34-0.16% of rare earths) is given by R.
The preparations of morphine are incompatible with salts of iron, copper and mercury, also with lime water and alkaline earths and substances containing tannin.
It belongs to the group of metals whose oxides are generally denominated "rare earths," and its history is bound up in the history of the group, which is especially interesting from the fact that it supplies the material for the manufacture of the mantles used in incandescent gaslighting, and also that the radio-active substances are almost invariably associated with these oxides.
It is found that for almost all purposes a system of measurement based ultimately on the earths rotation is perfectly adequate.
In the case of a particle falling directly towards the earth from rest at a very great distance we have C=o and, by Newtons Law of Gravitation, p/ai=g, where a is the earths radius.
The deviation of the earths figure from sphericity, and the variation of g with latitude, are here ignored.
We find that the velocity with which the particle would arrive at the earths surface (x=a)is ~ (2ga).
The oouple may be due to the earths magnetism, or to the torsion of a suspending wire, or to a bifilar suspension.
The earths precessional motion is of this latter type, the angles being ci = .0087, ~=23 28.
Hence if the earths axis of rotation deviates slightly from the axis of figure, it should describe a cone about the latter in 320 sidereal days.
This would cause a periodic variation in the latitude of any place on the earths surface, as determined by astronomical methods.
How the Earths Resistance is to be treated..
.V,Then the pressure exerted by a structure on the earth (to which the earths resistance is equal and opposite) consists either of one pressure, which is necessarily the resultant of the weight of the structure and of all the other forces applied to it, or of two or more parallel vertical forces, whose amount can be determined at the outset of the investigation, the resistance of the earth can be treated as one or more upward loads applied to the structure.
BARIUM (symbol Ba, atomic weight 137.37 [0=,6]), one of the metallic chemical elements included in the group of the alkaline earths.
As soon as he was able to work again he attempted to obtain the metals of the alkaline earths by the same methods as he had used for those of the fixed alkalis, but they eluded his efforts and he only succeeded in preparing them as amalgams with mercury, by a process due to Berzelius.
As a general class, the sulphates are soluble in water, and exhibit well crystallized forms. Of the most insoluble we may notice the salts of the metals of the alkaline earths, barium, strontium and calcium, barium sulphate being practically insoluble, and calcium sulphate sparingly but quite appreciably soluble.
If oils and fats are treated with water alone under high pressure (corresponding to a temperature of about 220° C.), or in the presence of water with caustic alkalis or alkaline earths or basic metallic oxides (which bodies act as "catalysers") at lower pressures, they are converted in the first instance into free fatty acids and glycerin.
In special cases, such as the preparation of edible oils and fats, a further improvement in colour and greater purity is obtained by filtering the oils over charcoal, or over natural absorbent earths, such as fuller's earth.
Similar methods are employed in the production of lard oil, edible cotton-seed oil, &c. For refining oils and fats intended for edible purposes only the foregoing methods, which may be summarized by the name of physical methods, can be used; the only' chemicals permissible are alkalis or alkaline earths to remove free fatty acids present.
Selection of Deer control areas Give primary importance to underlying soil type, with preference to surface water gleys and brown earths.
The soundcard part of the interface completely isolates the earths on the PC and the transceiver and eliminates ground loops.
All of us began as the same upright primate, roaming tropical savannas on a million identical earths, and look at us now.
This group studies the convection regime within the Earths Mantle in three dimensional spherical geometry at approaching Earth-like vigor.
In its character yttrium is closely allied to, and in nature is always associated with, cerium, lanthanum, didymium and erbium (see Rare Earths).
While convincing us that the plants of past ages in the earths history were exposed to very similar conditions of life, and made very much the same adaptive responses as their modern representatives, one of the main results of this line of work has been to reveal important data enabling us to fill various gaps in our morphological knowledge and to obtain a more complete picture of the evolution of tissues in the vascular plants.
This aggregation of genera and of endemic species is characteristic of the circumferential portions of the earths land surface: the expansion of the one and the further advance of the other is arrested.
The former substituted for the salt, sulphur and mercury of Basil Valentine and Paracelsus three earths - the mercurial, the vitreous and the combustible - and he explained combustion as depending on the escape of this last combustible element; while Stahl's conception of phlogiston - not fire itself, but the principle of fire - by virtue of which combustible bodies burned, was a near relative of the mercury of the philosophers, the soul or essence of ordinary mercury.
The spectroscope has played an all-important part in the characterization of the elements, which, in combination with oxygen, constitute the group of substances collectively named the " rare earths."
(() An infusible white residue may be obtained,which may denote barium, strontium, calcium, magnesium, aluminium or zinc. The first three give characteristic flame colorations (see below); the last three, when moistened with cobalt nitrate and re-ignited, give coloured masses; aluminium (or silica) gives a brilliant blue; zinc gives a green; whilst magnesium phosphates or arsenate (and to a less degree the phosphates of the alkaline earths) give a violet mass.
Their number is further increased by spatial inversion of the dicarboxylic acids formed on oxidation, followed by reduction; for example: d- and /-glucose yield d-and l-gulose; and also by Lobry de Bruyn and Van Ekenstein's discovery that hexoses are transformed into mixtures of their isomers when treated with alkalis, alkaline earths, lead oxide, &c.
SAMARIUM [[[symbol]] Sm, atomic weight 150.4 (0= 16)1, a rare earth metal (see Rare Earths).
YTTERBIUM (NEO-YTTERBIUM) [[[symbol]], Yb; atomic weight, 172.0 (0 = '6)1, a metallic chemical element belonging to the rare earth group. Mixed with scandium it was discovered by Marignac in gadolinite in 1878 (see Rare Earths).
If oils and fats are treated with water alone under high pressure (corresponding to a temperature of about 220Ã‚° C.), or in the presence of water with caustic alkalis or alkaline earths or basic metallic oxides (which bodies act as "catalysers") at lower pressures, they are converted in the first instance into free fatty acids and glycerin.
When the Crisis on Infinite Earths occurred, the multiverse began to collapse, ending the existence of many Earth Two heroes.
The most important imports are minerals, including coal and metals (both in pig and wrought); silks, raw, spun and woven; stone, potters earths, earthenware and glass; corn, flour and farinaceous products; cotton, raw, spun and woven; and live stock.
The medicinal preparations which required the aid of a furnace, such as mineral earths, were undertaken by the chymists, who probably derived their name from the Alchymists, who flourished from the 14th to the 16th centuries.
The former is concerned with the division of the earths surface into major districts characterized by particular plants or taxonomic groups of plants, with the subdivision of these floristic districts, and with the geographical distribution (both past and present) of the various taxonomic units, such as species, genera, and families.
The problem, then, which plantdistribution presents is twofold: it has first to map out the earths surface into regions or areas of vegetation, and secondly to trace the causes which have brought them about and led to their restriction and to their mutual relations.
From this point of view it is not sufficient, in attempting to map out the earths surface into regions of vegetation, to have regard alone to adaptations to physical conditions.
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