In 1840 the freedom of mining was introduced, 2 By the law of 1906 the state has not assumed the responsibility of the construction of reservoirs for irrigation.
Numerous canals intersect the district, affording ample means of irrigation.
The Panlaung and Zawgyi rivers from the Shan States flow through the district and are utilized for the numerous irrigation canals.
The vegetation of each region has its distinctive character, modified here and there by elevation, irrigation from mountain streams, and by the saline character of the soil.
Among a variety of premiums awarded by the state are those for the best cultivated estates and for irrigation works, and to the owners of the best stallions and brood-mares.
It is exceedingly picturesque, the villages clinging to the sides of the mountain glens from which water is drawn for irrigation; and excellent fruit is grown.
Irrigation works have been carried out in various parts.
It is only navigable by small sailing-vessels, even in its estuary, but its waters are extensively utilized for irrigation.
From its source to the city of Kabul the course of the river is only 45 m., and this part of it is often exhausted in summer for purposes of irrigation.
Milan undertook the irrigation works which enriched the soil of Lombardy for ever.
The valley bed is more or less covered with alluvial soil, and cultivated in places by artificial irrigation.
The method of this irrigation is peculiar.
Through this part of its course the current of the river, except where restricted by floating bridges - at Feluja, Mussaib, Hillah, Diwanieh and Samawa - does not normally exceed a mile an hour, and both on the main stream and on its canals the jerd or oxbucket takes the place of the naoura or water-wheel for purposes of irrigation.
The object is to allow sufficient water to drain off to the westward for the due irrigation of the land, while the Hillah bed still retains the main volume of the stream, and is navigable to the sea.
The fact also that many of the most ancient of these ruins, like Ur, Lagash (Sirpurla), Larsa, Erech, Nippur, Sippara and Babylon, were situated on the banks of the great canals would indicate that the control of the waters of the rivers by a system of canalization and irrigation was one of the first achievements of civilization.
There are several lakes of great depth and streams well fitted for the purposes of irrigation, of which full advantage is taken by the natives.
Save where irrigation has reclaimed small areas, the whole region is a vast desert, though locally only some of the interior plains are known as "deserts."
Except on the scattered oases, where irrigation from springs and mountain streams has reclaimed small patches, the desert is barren and forbidding in the extreme.
The Truckee river flows with more vigour, having its source in Lake Tahoe, in California, at an altitude of 6225 ft., and entering the Carson river through an irrigation canal :completed in 1905; before this date it flowed into Pyramid Lake and Lake Winnemucca in the depression at the foot of the Sierra Nevada.
Because of this extreme aridity, agriculture in Nevada is dependent on irrigation.
The three principal areas in which irrigation is practicable are along the Humboldt river, in the plains watered by the Carson, Truckee and Walker rivers, and at the foot of the mountains along the western edge of the state.
The survey for the Truckee-Carson system was begun in 1902, with the object of utilizing the waters flowing to waste in western Nevada for the irrigation and reclamation of the adjacent arid regions in Churchill, Lyon and Storey counties.
In this tract the rainfall is nowhere sufficient for the purposes of agriculture, which is only possible by help of irrigation; and the fixed population (which contains a non-Turkish element) is comparatively small, and restricted to the towns and the districts near the rivers.
24 along the slopes of the higher mountains, on which the rain falls more abundantly, or the melting snow supplies streams for irrigation.
The other cereals may be seen occasionally, where artificial irrigation is practised, in all stages of progress at all seasons of the year, though the operations of agriculture are, as a general rule, limited to the rainy months, when alone is the requisite supply of water commonly forthcoming.
They had also much skill in the construction of works for the supply of drinking water on a large scale and for irrigation.
The steppes along the bottom of the principal valley are for the most part too dry to be cultivated without irrigation.
The Mugan steppe is, however, in spite of its dryness, a more fertile region in virtue of the irrigation practised; but the Kura has excavated its bed too deeply to admit of that being done along its course.
But where irrigation is employed the yield of crops is excellent.
The agriculture of the region bordering the Tigris and Euphrates, like that of Egypt, depended largely on irrigation, and traces of ancient canals are still to be seen in Babylonia.
The earliest known forms of intensive husbandry were based chiefly upon the proximity of rivers and irrigation.
Attica was famous for its olives and figs, but general agriculture excelled in Peloponnesus, where, by means of irrigation and drainage, all the available land was utilized.
Irrigation benefits a sandy soil, draining a marshy soil.
The work on agriculture' of Ibn-al-Awam, who lived in the 12th century A.D., treats of the varieties of soils, manuring, irrigation, ploughing, sowing, harvesting, stock, horticulture, arboriculture and plant diseases, and is a lasting record of their skill and industry.
Both draining and irrigation are noticed, though the latter but slightly.
finished, with the object of amassing sufficient capital to construct a dike for his native town of Tus, which suffered greatly from defective irrigation, a project which had been the chief dream of his childhood.
The great canal was not begun; irrigation works were started but were soon given up. The letters of Kleber and Menou (the successors of Bonaparte) show that the expenditure on public works had been so reckless that the colony was virtually bankrupt at the time of Bonaparte's departure; and William Hamilton, who travelled through Egypt in 1802, found few traces, other than military, of the French occupation.
In the littoral districts excellent crops of cereals, cotton, fruit, wine and tobacco are obtained with the aid of irrigation.
- Climatic conditions in Egypt differ radically from those in the United States, the rainfall being so small as to be quite insufficient for the needs of the plant, very little rain indeed falling in the Nile Delta during the whole growing season of the crop: yet Egypt is in order the third cottonproducing country of the world, elaborate irrigation works supplying the crop with the requisite water.
It is considered that with facilities for irrigation Andalusia could produce 150,000 bales annually.
The rainfall is uncertain and low, however, never exceeding 40 in., and on the supply of water by irrigation the future of the industry mainly depends.
Still more recently, however, experiments have been made to grow Egyptian cotton in Sind with the help of irrigation.
Owing to the high barrier which shuts off almost all Syria from the sea, and precipitates vapours mainly on the western slope, little of the land is highly productive without irrigation, except the narrow littoral strip which was the ancient Phoenicia, and the small deltas, such as that of Latakia (Laodicea).
For the rest, Syria needs irrigation; and since neither of its larger rivers, Orontes or Jordan, flowing as these do in deep beds, is of much use for this purpose, all Mid-Syria, except the lacustrine oases, is a region mainly occupied by pastures, and yielding only thin cereal crops.
Irrigation, introduced in 1888 by the orange growers, has been adapted by other farmers, especially the tobacco-growers of Gadsden county, and so the evil effects of the droughts, so common from February to June, are avoided.
It has published a topographical map of the Nile valley (1:50,000), an irrigation map (I:10o,000), a general map (1: 2 50,000), numerous cadastral plans, &c. Work on similar lines is carried on in the Anglo-Egyptian Sudan.
In this region irrigation is widely used.
In the town of Raymond is a large beet sugar manufactory, and in the vicinity great quantities of beets are grown by irrigation.
These prairies are traversed by ridges, which facilitate irrigation, and are underlaid by an impervious subsoil, which facilitates both effective storage and drainage.
Irrigation is almost entirely confined to rice farms. In the prairie region there is abundant water at depths of too to 400 ft.
beneath the surface, but this was little used for irrigation for the first few years of the development of this field, when water was pumped from the streams and canals.
The irrigated rice area increased 92.9% from 1899 to 1902, and the construction cost of irrigation works ($4747,359 in 1902; $12.25 per irrigated acre) 87.7% in the same years.
Many bayous are convertible by improvement into excellent drainage and irrigation canals.
Water Supply and Irrigation Papers, No.
Much of the soil of the desert appears to be alluvial; there are numerous traces of streams having formerly passed over it, and still, where irrigation is at all practicable, fertility in the clayey tract follows; but the rains are scanty, the wells few and generally 100 ft.
The benefits of canal irrigation were introduced in the 'seventies, and the revenue thus doubled.
To add to the uncertainties of navigation, the inhabitants along the eastern bank of the stream frequently dig new canals for irrigation purposes, which both reduces the water of the river and tends to make it shift its channel.
The northern sides and tops of the lower heights are often covered with dense forests of oak, cork, pine, cedar and other trees, with walnuts up to the limit of irrigation.
This supersedes artificial irrigation, and the plains so watered yield abundantly in rice, jute and mustard.
In the neighbourhood of the Vaal, confluence, where the river passes through alluvial land, and at some other places, the waters of the Orange are used, and are capable of being much more largely used, for irrigation purposes.
There are also the ruins of a band, or stone dam of great strength, which was thrown across the river for the purposes of irrigation.
The state came under British management, and the administration was improved, the revenue increased, a system of irrigation developed, new tanks and wells constructed and an excellent system of roads and public buildings organized.
It also conducts campaigns against locusts and other pests and helps irrigation settlements.
It is a region of lakes and morasses, of arid plains and high temperatures, but experiments with irrigation toward the end of the 19th century were highly successful and considerable tracts have since been brought under cultivation.
The Nerbudda is nowhere utilized for irrigation, and navigation is confined to the lower section.
Many regions suffer permanently from deficient rainfall; in others, owing to the absence of irrigation works, the water supply is lost, while the burning of the grass at the end of summer, a practice adopted by many farmers, tends to impoverish the soil and render it arid.
The act authorizing the loan devoted £2,500,000 to the establishment of a land and agricultural bank, and £2,500,000 to railways, public works, irrigation and agricultural settlement and development.
He also recognized the necessity, if agriculture was to be developed, of an extensive system of irrigation, and Sir William Willcocks, formerly of the Egyptian Irrigation Department, was engaged to draw up a comprehensive scheme, having in view also the needs of the gold mines.
Collins, " Irrigation in the Transvaal," Minutes of P. I.
Irrigation, which has not been used to any great extent, is needed in some parts of the country for the best results, but in others, as in the valleys and on the northern slopes of the Maritime Andes, the rainfall is sufficiently well distributed to meet most requirements.
The long dry season of the llanos and surrounding slopes, which have not as yet been devoted to cultivation, will require a different system of agriculture with systematic irrigation.
The climatic conditions are not so favourable as in Argentina, but these are counterbalanced to some extent by the great river system of the Orinoco, whose large navigable tributaries cross the plains from end to end, and whose smaller streams from the surrounding highlands provide superior opportunities for water storage and irrigation.
The tree has an average height of 12-13 ft., begins bearing five years after planting, requires little attention beyond occasional irrigation, bears two crops a year (June and December), and produces well until it is forty years of age - the yield being from 490 to 600 lb per acre of 100 trees.
Agriculture has been developed only to a limited extent in Sonora, because of its aridity, lack of irrigation facilities, lack of railways and roads, and the unsettled state of the country.
Other important sources of revenue are the rents from state lands, forests, and miscellaneous items such as fishery, revenue and irrigation taxes.
In some parts of Lower Burma and in the dry districts of Upper Burma a hot season crop is also grown with the assistance of irrigation during the spring months.
At the time of the British annexation of Burma there were some old irrigation systems in the Kyaukse and Minbu districts, which had been allowed to fall into disrepair, and these have now been renewed and extended.
In all upwards of 300,000 acres are subject to irrigation under these schemes.
The dense population was due to the elaborate irrigation of the Babylonian plain which had originally reclaimed it from a pestiferous and uninhabitable swamp and had made it the most fertile country in the world.
The science of irrigation and engineering seems to have been first created in Babylonia, which was covered by a network of canals, all skilfully planned and regulated.
Thanks to this system of irrigation the cultivation of the soil was highly advanced in Babylonia.
A rapid in the Tagus, artificially converted into a weir, renders irrigation easy, and has thus created an oasis in the midst of the barren plateau of New Castile.
The country is dry and sandy, and entirely depends on well irrigation for its water supply.
Here the tropical heat is tempered by constant trade winds, there is perfect immunity from hurricanes, the soil is peculiarly suited for cane-growing, and by the use of specially-prepared fertilizers and an ample supply of water at command for irrigation the land yields from 50 to 90 tons of canes per acre, from which from 12 to 14% of sugar is produced.
With an inexhaustible supply of irrigation water obtainable, there is no reason why the lands in Upper Egypt, if scientifically cultivated and managed, should not yield as abundantly as those in the Sandwich Islands.
The landscape is rich and beautiful, varied with grand rock scenery, the coast-line being broken by numerous small bays, into which flow streams rarely navigable even for short distances, but often skilfully utilized by the natives for irrigation; and sometimes flowing in subterranean channels.
This may be more than the rainfall, in which case irrigation or special control of the water supply may be necessary.
In the semi-arid regions of the United States, Argentina and other countries where the average annual rainfall lies between ioa to 20 in., irrigation is necessary to obtain full crops every year.
Good crops, however, can often be grown in such areas without irrigation if attention is paid to the proper circulation of water in the soil and means for retaining it or preventing excessive loss by evaporation.
In good seasons it is sufficient for the cultivation of the summer crop of millet, and for the supply of the perennial streams and springs, on which the irrigation of the winter crops of wheat and barley depend.
But for a long period past the freshwater streams (which predominate) have been used for irrigation to such a degree that very little of the precious water is allowed to run to waste into the lake basins; so that these latter receive only a few salt streams, which deposit on their surface the salt they contain and then evaporate.
All these valleys, except Morrope and Chao, are watered by rivers which have their sources far in the recesses of the mountains, and which furnish an abundant supply in the season when irrigation is needed.
Communications.-The problem of easy and cheap transportation between the coast and the interior has been a vital one for Peru, for upon it depends the economic development of some of the richest parts of the republic. The arid character of the coastal zone, with an average width of about 80 m., permits cultivation of the soil only where water for irrigation is available.
This seems incompatible with the arid character of the country and the peculiar conditions of its civilization, but irrigation has been successfully employed in the fertile valleys of the coast.
Irrigation is necessary for productiveness, and the water-supply is now deficient.
They are all used for irrigation.
Cereals are grown in some localities, and there are large vineyards where irrigation is possible, from which excellent wine is made.
The great bend of the river affords easy irrigation, and the surrounding country is covered by a network of irrigating canals, even the paved streets of the town having streams of cool water running through them.
Numerous canals are cut from the rivers for the purpose of affording artificial irrigation, which has proved of immense benefit to the country.
Well and tank water is also largely used for irrigation purposes.
An irrigation canal, deriving water from the Sega, furnishes 112 cubic metres per second to the fields of the upper Veronese district.
In 1901 the population was 1,200,822, showing an increase of 15% in the decade, due to the extension of irrigation.
The UPPER GANGES CANAL and the LOWER GANGES CANAL are the two principal systems of perennial irrigation in the United Provinces.
Pursuing an easterly course, this stream receives the waters of the romantic `Ain Fije (which doubles its volume), and bursts out by a rocky gateway upon the plain of Damascus, in the irrigation of which it is the chief agent.
The valleys are highly fertile, and where irrigation is employed large crops are easily raised.
Beyond the limits of irrigation the country is semi-barren.
The Orissa canal system, which lies mainly within Cuttack district, is used both for irrigation and transport purposes.
The rainfall is light in the lower regions and irrigation is generally employed.
A complete system of irrigation permeates the whole cultivated part of a village, the water being often brought from a long distance by stone aqueducts.
The Ebro and its tributaries have been utilized for irrigation since the Moorish conquest; the main stream becomes navigable by small boats about Tudela; but its value as a means of communication is almost neutralized by the obstacles in its channel, and seafaring vessels cannot proceed farther up than Tortosa.
below Saragossa; the irrigation canal of Tauste skirts the opposite bank for a shorter distance; and the San Carlos or New Canal affords direct communication between Amposta at the head of the delta and the harbour of Los Alfaques.
It is impossible, whilst watching the rolling, seething volume of flood-water which swirls westwards in April, to imagine the waste stretches of dry river-bed which in a few months' time (when every available drop of water is carried off for irrigation) will represent the Hari Rud.
The system of irrigation by which these agricultural results are attained is most elaborate.
He adopts the karez (or, Persian, kandt) system of underground irrigation, as does the Ghilzai, and brings every drop of water that he can find to the surface; but it cannot be said that he is more successful than the Ghilzai.
Through this stretch of dasht the drainage from the main water-divide breaks downwards to the plains of Herat, where it is arrested and utilized for irrigation purposes.
Notwithstanding the large number of streams, the depression of their channels and height of their banks render them for the most part unsuitable for the purposes of irrigation, - which is conducted by means of jhils and tanks.
But due to lack of policies for proper water management the irrigation system is too poor.
Mainly unnavigable and of little use for irrigation, the Orontes derives its historical importance solely from the convenience of its valley for traffic from N.
All the water in excess of the city's actual needs may be employed for irrigation.
Lake Chalco is also greatly reduced in size by railway fillings and irrigation works, to the great distress of the natives who have gained their living by fishing in its waters since long before the Spanish conquest.
The rainfall, however, is light, about 20 to 25 in., but, with the assistance of irrigation, it serves to sustain a considerable degree of cultivation in the neighbourhood of the city.
In 1856 President Ignacio Comonfort invited tenders for drainage works conditional on the use of waste waters for irrigation purposes, and the plan executed consists of a canal and tunnel 43 m.
'BOKHARA' (Bokhara-i-Sherif), capital of the state of Bokhara, on the left bank of the Zarafshan, and on the irrigation canal of Shahri-rud, situated in a fertile plain.
Irrigation and terrace culture were practised at several points on the Pacific slope from Arizona to Peru.
He was as successful in the arts of peace as he had been in those of war; and carried to completion, among other good works, an ambitious irrigation scheme - probably the greatest feat of engineering that had then been accomplished anywhere in the world.
The Royal Canal of Tauste, which lies along the north side of the Ebro, was cut for purposes of irrigation, and gives fertility to the district.
Almost useless for communication or transport, they can be easily drawn upon for irrigation where, as in the east centre, water-races are useful.
The principal Federal irrigation undertakings in 1910 were known as the " Okanogan project " and the " Yakima project."
The former (authorized in 1905) provided for the irrigation of about 10,000 acres in Okanogan county by means of two reservoirs of an aggregate area of 650 acres, main canals and main laterals 20 m.
The Yakima project involved the irrigation of about 600,000 acres by means of five reservoirs of an aggregate area of 804,000 acre-feet, and was undertaken by the United States government in 1905.
Waller, Irrigation in the State of Washington (Washington, 1909), Bulletin 214 of the U.S. Department of Agriculture; and Water Supply and Irrigation Papers, 55 and 118 (1901 and 1905) of the U.S. Geological Survey.
The rainfall is sufficient for good grazing, but except in the Flathead valley cultivation was long considered to be dependent on irrigation; and consequently farming was only incidental to stock raising and mining until after 1870, and as late as 1900 the ratio of improved farm land to the total land area was less than in any other state or territory except New Mexico, Wyoming, Arizona and Hawaii.
In 1906 the farm area was almost equally divided between " dry " farming and farming under irrigation, three-fourths of the wheat produced was grown without irrigation, and the dry farming was very successful with the comparatively new and valuable crops of durum, or macaroni wheat, and Russian barley, which is used in straw for winter feed to sheep and neat cattle.
But even where dry farming was successful, the increase of crops made possible by cheap irrigation seemed to be inducing farmers to abandon it.
Among the larger privately irrigated tracts are: 16,000 to 18,000 acres in Yellowstone county, fed by a canal built by the Billings Land & Irrigation Company; about 35,000 acres of orchard land in the Bitterroot Valley, in Ravalli county, irrigated by canals from Lake Como, a natural reservoir; and 100,000 acres in Missoula county, to be watered from a 28 ft.
Private irrigation by pumping was first successfully introduced about 1901, and in 1906 a state report estimated that 125 pumping irrigation plants were in use in the state.
Boring for underground water supply to be used in irrigation was tried on a small scale.
long built in1902-1905by the co-operative Grass Valley-Frenchtown Irrigation Company, and the Teton Co-operative Canal Company in 1906 began work on a diversion canal from the Teton River, whose waters are to be stored by a dam 62 ft.
But more important than private and co-operative undertakings are the Federal irrigation projects.
In 1894 Congress passed the Carey Act, under which Montana received title to i,000,000 acres of arid land on condition that the state would reclaim it by providing an adequate supply of water; the state accepted the offer, created an irrigation commission, and provided means for securing the necessary funds.
Furthermore, Congress in 1902 appropriated the receipts from the sales of public lands in the state to the construction of irrigation work.
of irrigation canals and large ditches in the state; the irrigated acreage had increased from 350,582 acres in 1889 to 951,154 acres in 1899, when about 84% of the irrigated area was in the south-west.
Among them are: the Huntley project in Yellowstone county, begun in 1904 and practically completed in 1908, covering land formerly in the Crow Indian reservation, the irrigable area being 28,921 acres; the Lower Milk river project (and the subsidiary St Mary project), in Chouteau, Valley and Teton counties, by which the water of St Mary river 1 is stored and diverted to the headquarters of the Milk river to irrigate an area of 300,000 acres; the Sun river project (Teton, Lewis and Clark, Chouteau and Cascade counties), by which, as the ordinary flow of that river is already utilized for irrigation, the flood waters are stored and carried to the higher bench lands of the district; in Montana (Dawson county) and North Dakota (McKenzie county), the Lower Yellowstone project; and the Blackfeet project, to irrigate the Blackfeet reservation in Teton county.
Sugar beets were first grown in Montana at Evans, Cascade county, in 1893 without irrigation.
in Idaho), Bitterroot (1,180,900 acres), Blackfeet (1,956,340 acres), 1 The St Mary and both forks of the Milk river flow northward into the Dominion of Canada, and as there has been much private irrigation both north and south of the international boundary, the present Federal project and other undertakings in the same region necessitate an international agreement as to the division of the waters, especially of the St Mary, and commissioners representing the Canadian government and the United States conferred in regard to it in May 1908.
Many of the Indians are engaged in stock-raising; the Crows have an irrigation system and are extensively engaged in farming.
Bulletin 301) of the U.S. Geological Survey; Annual Reports of the Bureau of Agriculture, Labor and Industry of the State of Montana; Samuel Fortier, Irrigation in Montana (Washington, 1906), being Bulletin No.
Under the Reclamation Act passed by Congress in 1902 the irrigation of 10o,000 acres in the Belle Fourche Valley adjacent to the Black Hills region was provided for.
wide on top, and for two main canals from this distributing centre, one the north canal supplying water for the irrigation of 66,857 acres north of the Belle Fourche river and east of Owl Creek, and the other the south canal for the irrigation of 28,240 acres south of the Belle Fourche.
AGRA CANAL, an important Indian irrigation work, available also for navigation, in Delhi, Gurgaon, Muttra and Agra districts, and Bharatpur state.
At the western end of the barrage begins the Ibrahimia canal, the feeder of the Bahr Yusuf, the largest irrigation canal of Egypt.
Extensive irrigation works existed in Shwebo district, but they fell into disrepair in King Thibaw's time.
Irrigation is confined to the western half of the state, and more especially to the north-west, being employed chiefly in the drainage basin of the Missouri river.
The bed of the river is too far below the surrounding country to permit the use of its waters for irrigation purposes by the usual gravity methods.
The so-called Reclamation Act passed by Congress in 1902 provided for the construction of a system of irrigation works in this and other states by the Federal government.
Water for irrigation purposes is often derived from artesian wells, which are very numerous in the S.
Irrigation is rudimentary, for no system exists for raising the water of the innumerable canals on to the fields.
In 1905 the government started preliminary surveys for a system of irrigation.
Moreover, a college under the control of the Ministry of Lands and Agriculture, which was founded in 1909, provides locally courses of instruction in these subjects and also in irrigation engineering, sericulture and surveying.
This sum was employed chiefly in railway construction, and in 1907 a second loan of £3,000,000 was issued in London, Paris and Berlin at 931 for the same purpose and for extension of irrigation works.
Philo, De posteriori Caini, § 3, explains the name as meaning iroru ryos,"watering" or "irrigation," connecting it with the Hebrew root Sh Th Josephus, Ant.
On the lower courses of the Habra and the Sig, barrages have been built for irrigation purposes.
At Saint Martory it gives off the irrigation canal of that name.
Agriculture was formerly developed on the Tekez, as is testified by old irrigation canals.
The western portion of the state is a plain watered by the Zarafshan and by countless irrigation canals drawn from it.
Land suitable for cultivation is found only in oases, where it is watered by irrigation canals, but these oases are very fertile.
long, the water of which is largely utilized for irrigation, is lost in the sands 20 m.
Irrigation, careful husbandry and railroad communications have much developed the resources of their country, in themselves excellent; and there are many manufacturing towns and industrial establishments.
Then, there are the mangrove-fringed coasts and the dripping wooded slopes where rare orchids thrive, and above these, on the inland side of the sierra, a treeless, sun-scorched table-land where only the cactus, yucca, and other coarse vegetation of the desert can thrive without irrigation.
A large part of the country is too arid for agriculture, and even with irrigation the water supply is sufficient for only a small part of the dry area.
The problem for the agriculturist here is not irrigation, but drainage and keeping down spontaneous growths.
The Mexicans understood digging channels for irrigation, especially for the cultivation of the cacahuatl, from which they taught the Europeans to prepare the beverage chocollatl; these native names passed into English as the words cacao, or coco and chocolate.
The water supply is scanty, and most of the irrigation is by water drawn from wells.
The remainder of the residency is well-watered and fertile, important irrigation works having been carried out.
The open valleys between the spaced ranges offer many tempting sites for settlement, but in the south irrigation is needed for cultivation.
The ranges of the Rocky Mountains in their turn receive some rainfall from the passing winds, but it is only after the westerlies are reinforced by a moist indraft from the Gulf of Mexico and the Atlanticthe result of summer or of cyclonic inflowthat rainfall increases to a sufficient measure on the lower lands to support agriculture without irrigation.
The wall is nearly encircled by a stream of water, artificially diverted from the small rivulets which flow through the precincts, furnishing the establishment with an abundant supply in every part, for the irrigation of the gardens and orchards, the sanitary requirements of the brotherhood and for the use of the offices and workshops.
Wehr, defence), a barrier placed across rivers to raise the water-level for catching fish, for mills, for navigation or for irrigation, the discharge of the river taking place over the crest or through openings made for the purpose.
Weirs are essential for raising the head of water for water-wheels at mills, and for diverting some of the flow of a river into irrigation canals; but they have received their greatest and most varied extension in the canalization of rivers for navigation.
There are three distinct classes of weirs, namely, solid weirs, draw-door weirs, including regulating sluices for irrigation, and movable weirs, which retain the water above them for navigation during the low stage of the river, and can be lowered or removed so as to leave the channel quite open in flood-time.
The barrage at the head of the Nile delta, and the regulating sluices across the Nile at Assiut and Esna in Upper Egypt below Assuan, are examples of draw-door weirs, with their numerous openings closed by sluice-gates sliding on free rollers, which control the discharge of water from the river for irrigation.
The precipitation in southern Saskatchewan and Alberta is much more variable than farther east and north, so that in some seasons crops have been a failure through drought, but large areas are now being brought under irrigation to avoid such losses.
The interior plateau may be described as arid, so that irrigation is required if crops are to be raised.
In some parts of the semiarid districts in the interior of the province irrigation is being successfully practised for the purpose of bringing land under profitable cultivation for fruit.
the plain of Tarbes, and for the remainder of its course in the department of Hautes Pyrenees is of much less importance as a waterway than as a means of feeding the numerous irrigation canals which cover the plains on each side.
No special tillage is required, but weeding and irrigation are requisite.
In tropical countries drought is the commonest cause of a failure in the harvest, and where great droughts are not uncommon - as in parts of India and Australia - the hydraulic engineer comes to the rescue by devising systems of water-storage and irrigation.
Irrigation is better able to bring fertility to a naturally arid district than to avert the failure of crops in one which is naturally fertile.
The sum of 12 crores is regularly set aside for this purpose, and is devoted as a rule to the construction of protective irrigation works, and for investigating and preparing new projects falling under the head of protective works.
The measures by which the government of India chiefly endeavours to reduce the liability of the country to famine are the promotion of railways; the extension of canal and well irrigation; the reclamation of waste lands, with the establishment of fuel and fodder reserves; the introduction of agricultural improvements; the multiplication of industries; emigration; and finally the improvement where necessary of the revenue and rent systems. In times of famine the function of the railways in distributing the grain is just as important as the function of the irrigation-canals in increasing the amount grown.
Irrigation protects large tracts against famine, and has immensely increased the wheat output of the Punjab; the Irrigation Commission of 1903 recommended the addition of 62 million acres to the irrigated area of India, and that recommendation is being carried out at an annual cost of 12 millions sterling for twenty years, but at the end of that time the list of works that will return a lucrative interest on capital will be practically exhausted.
Local conditions do not make irrigation everywhere possible.
Holderness, Narrative of the Famine of 1896-1897 (c. 8812 of 1898); the Indian Famine Commission reports of 1880, 1898 and 1900; report of the Indian Irrigation Commission (1901-1903); C. W.
But beyond the sphere of irrigation, where the land is dependent on the rainfall, there is much rough stony ground broken by great fissures cut by flood-water from the border hills.
Canals are the main source of irrigation in the province, and fall under three heads: (I) Private canals in the various districts, the property of the people and managed on their behalf; (2) the Michni Dilazak and Shabkadar branch in Peshawar, constructed by the district board, which receives water rates; and (3) the Swat and Kabul river canals, which were constructed by and are the property of government, and are managed by the irrigation department.
In Kohat and Hazara any considerable extension of canal irrigation is out of the question, but in the remaining districts much can still be done to promote irrigation.
The steppes of the Kura are also fertile, but require artificial irrigation, especially for cotton.
The average yield per acre of cane-sugar is the greatest in the world, 30 to 40.tons of cane being an average per acre, and as much as rot tons of sugar having been produced from a single acre under irrigation.
The cultivation of the cane was greatly encouraged by the Reciprocity Treaty of 1875, which established practically free trade between the islands and the United States, and since 1879 it has been widely extended by means of irrigation, the water being obtained both by pumping from numerous artesian wells and by conducting surface water through canals and ditches.
4 These and other title-holders received corresponding rights to the use of irrigation ditches, and to fish in certain sea areas adjacent to their holdings.
Even at the time when they were first known to Europeans, they had stone and lava hatchets, shark's-tooth knives, hardwood spades, kapa cloth or paper, mats, fans, fish-hooks and nets, woven baskets, &c., and they had introduced a rough sort of irrigation of the inland country with long canals from highlands to plains.
Willcocks' irrigation schemes had not up to 1910 affected "Mesopotamia" directly.
The rough northern districts, where an occasional stream affords irrigation for a fertile soil, are noted for a remarkably uniform, dry, mild and healthful climate.
Irrigation is used to a large extent.
In both the Castiles the central plateau has a naturally fertile soil, for after rain a luxuriant vegetation appears; but drought is common, owing to the insufficient volume of the rivers, and the failure of the Spaniards to extend the fine system of irrigation which the Moors originated.
Water is obtained from wells and springs in sufficient quantity to supply an extensive system of irrigation.
The plain around Milan is extremely fertile, owing at once to the richness of the alluvial soil deposited by the Po, Ticino, Olona and Adda, and to the excellent system of irrigation.
From this period also date the irrigation works which render the Lombard plain a fertile garden.
Nearly all the moisture that is precipitated during six or seven months is stored up in the form of snow, and is gradually diffused in the course of the succeeding summer; even in the hottest and driest seasons the reserves accumulated during a long preceding period of years in the form of glaciers are available to maintain the regular flow of the greater streams. Nor is this all; the lakes that fill several of the main valleys on the southern side of the Alps are somewhat above the level of the plains of Lombardy and Venetia, and afford an inexhaustible supply of water, which, from a remote period, has been used for that system of irrigation to which they owe their proverbial fertility.
Following the example of the great Kampen irrigation canal in Belgium, artificial irrigation is also practised by means of some of the smaller streams, especially in North Brabant, Drente and Overysel, and in the absence of streams, canals and sluices are sometimes specially constructed to perform the same service.
Stock-breeding, like agriculture, has considerably improved under the care of the government (state and provincial), which grants subsidies for breeding, irrigation of pasture-lands, the importation of finer breeds of cattle and horses, the erection of factories for dairy produce, schools, &c.
The Gedenboek uitgeven ter gelegenheid van het fijftig-jarig bestaan van het Koninklijk Instituut van Ingenieurs, 1847-1897 ('s Gravenhage, 1898), is an excellent aid in studying technically the remarkable works on Dutch rivers, canals, sluices, railways and harbours, and drainage and irrigation works.
Another canal, to the west of Leczyca, connects the Bzura, a tributary of the Vistula, with the Ner and the Warta; and the bed of the former has been altered so as to obtain regular irrigation of the meadows along its banks.
deep. The water is raised by rope and bucket at the cost of enormous labour, and in few cases is any available for irrigation.
When water can be obtained and distributed over an arid region by irrigation, the surface as a rule becomes extremely productive.
Where a river crosses a desert at a level near that of the general surface, irrigation can be carried on with extremely profitable results, as has been done in the valley of the Nile and in parts of the Great Basin of North America; in cases, however, where the river has cut deeply and flows far below the general surface, irrigation is too expensive.
The art of irrigation is so well understood that the water supply is at times exhausted, no river water being allowed to run to waste.
Irrigation by "karez" is also largely resorted to.
A very small amount of cultivation is carried on, mostly without irrigation.
There are extensive orange-groves, watered by the irrigation canal of Castellon, which is a good example of Moorish engineering skill.
It is still, territorially, the largest province of the empire, and includes some of the most fertile lands in the Euphrates-Tigris valleys; but while possessing great possibilities for fertility, by far the larger portion of the vilayet is to-day a desert, owing to the neglect of the irrigation canals on which the fertility of the valley depends.
Wherever there is any pretence at irrigation, along the banks of the two great rivers and by the few canals which are still in existence, the yield is enormous, and the shores of the Tigris and Euphrates in the neighbourhood of Bagdad and Hilla seem to be one great palm garden.
- Where there is abundance of rainfall, and when it falls at the required season, there is in general no need for irrigation.
Irrigation is an art that has been practised from very early times.
The sculptures and paintings of ancient Egypt bear no trace of anything approaching scientific irrigation, but they often show the peasant baling up the water at least as early as 2000 B.C. By means of this simple plan of raising water and pouring it over the fields thousands of acres are watered every year in India, and the system has many advantages in the eyes of the peasant.
In spite of a certain amount of investigation, the early history of irrigation in Persia and China remains imperfectly known.
In Spain irrigation may be traced directly to the Moorish occupation, and almost everywhere throughout Asia and Africa where the Moslem penetrated is to be found some knowledge 'of irrigation.
In the Mediterranean provinces of Spain there are some very remarkable irrigation dams. The great masonry dam of Alicante on the river Monegre, which dates from 1579, is situated in a narrow gorge, so that while 140 ft.
of water, and to serve for the irrigation of 9000 acres, but unless it refills several times a year, it is hardly possible that so much land can be watered in any one season.
high, said to be Boo years old, and to serve for the irrigation of 25,000 acres.
In the jungles of Ceylon are to be found remains of gigantic irrigation dams, and on the neighbouring mainland of Southern India, throughout the provinces of Madras and Mysore, the country is covered with irrigation reservoirs, or, as they are locally termed, tanks.
The casual traveller in southern India constantly remarks the ruins of old dams, and the impression is conveyed that at one time, before British rule prevailed, the irrigation of the country was much more perfect than it is now.
An irrigation reservoir, like a human being, has a certain life.
In the countries now being considered, the test of an irrigation work is how it serves in a season of drought and famine.
Irrigation effected by river-fed canals naturally depends on the regimen of the rivers.
Sometimes the flood Irrigation canals.
In countries nearly rainless, such as Egypt or Sind, there can be no cultivation without irrigation.
In ordinary years in southern India the maize and the millet, which form so large a portion of the p easants' food, can be raised without irrigation, but it is required for the more valuable rice or sugar-cane.
When a river partakes of the nature of a torrent, dwindling to a paltry stream at one season and swelling into an enormous flood at another, it is impossible to construct a system of irrigation canals without very costly engineering works, sluices, dams, waste-weirs, &c., so as to give the engineer entire control of the water.
Irrigation cannot be practised in more favourable circumstances than these.
The greater the heat, the more rapidly melts the ice, and the larger the quantity of water available for irrigation.
In the deltas of southern India irrigation is only practised during the monsoon season.
For this monsoon irrigation there is always abundance of water, and so long as the canals and sluices are kept in repair, there is little trouble in distributing it over the fields.
Similar in character was the ancient irrigation of Egypt practised merely during the Nile flood - a system which still prevails in part of Upper Egypt.
Where irrigation is carried on throughout the whole year, even when the supply of the river is at its lowest, the distribution of the water becomes a very delicate operation.
Some crops of course require water much oftener than others, and much depends on the temperature at the time of irrigation.
Experience in these sub-tropical countries shows the absolute necessity of having, for successful irrigation, also a system of thorough drainage.
Closer examination, however, shows that if the prevailing slopes are not more than a few inches in the mile, yet they do exist, and scientific irrigation requires that the canals should be taken along the crests and drains along the hollows.
The result of this drainless irrigation is an efflorescence of salt on the surface of the field.
The word usage examples above have been gathered from various sources to reflect current and historial usage. They do not represent the opinions of YourDictionary.com.