In the western highland region of the United States considerable areas already have been made productive by irrigation, and it is estimated that about two million acres of barren land can be reclaimed by impounding the waters of the various streams now running to waste.
The distribution of rain with respect to the season in which it falls is quite as important as its distribution with respect to quant.i.ty. In tropical regions the ocean winds, and therefore the rainfall, come from the east. The eastern slopes of such regions, therefore, have a season in which rains may be expected daily, and another in which no rain falls for several months. In the temperate zones seasonal rains for a similar reason are on the western coasts.
Thus on the Pacific coast of the United States the rainfall varies from about one hundred inches in southern Alaska to about twelve in San Diego, Cal. Practically all the rain falls between October and the following May; very little or none falls in the interval between May and October. As a result, ordinary turf-gra.s.s, which will not withstand long droughts, grows in only a few localities of the Pacific slope. It is replaced by hardier gra.s.ses whose roots, instead of forming turf, grow very deep in the soil.
Common clover will not grow in this region unless irrigated; it is replaced by burr-clover, a variety of the plant that will not thrive in moist regions. Now the quality of the merino wool clip of California depends in no slight degree upon the burr-clover and other food-products that thrive in regions of seasonal rains; that is, a great commercial industry exists because of this feature of rainfall, and it could not long survive in spite of it.
[Ill.u.s.tration: CLIMATICALLY ADAPTED TO CULTIVATION--THE LOWLANDS PRODUCE BREAD-STUFFS AND FRUIT; THE MOUNTAIN-SLOPES ARE GRAZING REGIONS]
The seasonal rainfall also affects other agricultural industries. The sacked wheat-crop may be left in the field without cover or protection until the time is convenient for shipping it. The absence of summer rains makes possible in California what would be out of question in the Mississippi Valley, where a rainstorm may be expected every few days.
The quality of certain fruits depends largely on the season during which the rainfall occurs. Apples, pears, and grapes grown in regions having dry summers have usually a very superior flavor. The raisin-making industry of California also depends on the same condition, because, in order to insure a good quality of the product, the bunches of grapes, after picking, must be dried on the ground. To a certain extent this is also true of other fruits, such as dates, figs, and prunes, which frequently are sun-dried.
The presence of large bodies of water, which both absorb and give out their heat very slowly, tempers the climate of the nearby land and to that extent modifies the commerce of such districts. The grape-growing industry of central New York is a great one and its product is famous.
Its existence depends almost wholly upon the lake-tempered climate.
Elsewhere in the State the industry is on a precarious basis, and the product is inferior.
=Effects of Inclination of the Earth"s Axis.=--The inclination and self-parallelism of the earth"s axis is undoubtedly a very important factor in climate. Practically it more than doubles the width of the belts of ordinary food-stuffs by lengthening the summer day in the temperate zone. Beyond the tropics the obliquity of the sun"s rays are more than balanced by the increased length of time in which they fall.
Thus, in the lat.i.tude of St. Paul, the longest day is about fifteen and one-half hours long; at Liverpool it is nearly seventeen hours long; a greater number of heat units therefore are received in these lat.i.tudes during summer than are received in equatorial regions during the twelve-hour day. Moreover, the summer temperature is higher in these lat.i.tudes than in the torrid zone, because the sun is shining upon them for a greater length of time.
The result of these various influences is far-reaching. Because of the long summer days and short nights, wheat can be cultivated to the sixtieth parallel. Corn, which gets scarcely enough warmth and light in the torrid zone to become a prolific crop, attains its greatest yield in the lat.i.tude of fourteen-hour days.
These factors, it is evident, carry the grain and meat industries into regions that otherwise would not be habitable. Because the long summer days produce these great food-crops, commerce and its allied industries have reached their maximum development in these regions. Human activities are greatest in the zones bounded by the thirty-fifth and fifty-fifth parallels, the zone that includes the greater parts of the United States, Europe, China, j.a.pan. They are greatest, moreover, because of their geographical position.
QUESTIONS FOR DISCUSSION
What would be the probable effect on the food-crops of the United States were the main body of the country moved twenty degrees north in lat.i.tude? Which would then be the wheat-growing States, the cotton-producing States?
Ill.u.s.trate the connection between occupation and alt.i.tude above sea-level.
What difference would it make to the corn-crop were the days and nights always twelve hours long?
What would be requisite to make Canada a centre of silk production?
Why is not cod-fishing an industry off the east coast of Florida?
Why is the greater part of the Russian Empire destined to be spa.r.s.ely peopled?
FOR COLLATERAL REFERENCE
A rain chart of the world.
A chart of isothermal lines.
CHAPTER V
TRANSPORTATION--OCEAN AND INLAND NAVIGATION
Of all the adjustments which come into the lives of a people none has been so far-reaching as the gradual localization of industries each in the region best adapted to it. For instance, manufacturing industries require power, but not fertile soil; therefore the manufacturing industries seek nearness to fuel or to water-power, and a position available for quick transportation.
Farming does not require any great amount of natural power; on the contrary, level land having a great depth of fertile soil is the essential feature. The farmer must therefore look first of all to conditions of topography and climate, and secondly to the means of transporting his crop.
Mining cannot be an industry in regions dest.i.tute of minerals; the miner must therefore go where the mineral wealth is found, without regard to climate, soil, centres of population, or topography. But two things are required--the mineral products and the means of getting them to the people--that is, ready means of transportation.
A century or more ago, each centre of population in the United States was practically self-sustaining. Each grew its own food-stuffs, and manufactured the articles used in the household. But very little was required in the way of transportation. The means of carriage were mainly ox-carts, pack-horses, and rafts. There was a mutual independence among the various centres, it is true, but the independence was at the expense of civilization and the comforts of life.
[Ill.u.s.tration: OCEAN TRANSPORTATION--ROYAL MAIL STEAMSHIP OCEANIC, WHITE STAR LINE]
Beyond an independence that is more apparent than real, such a plan of social and industrial organization has but little in it to commend.
Intercommunication increases knowledge, and under the conditions that formerly prevailed, there was a lack of the breadth of knowledge that comes with the mutual contact of peoples.
The utilization of national resources, such as the productiveness of the land, the existence of iron ore, coal, copper, and other economic minerals, finally brought about the policy of a territorial division of industries. This, in turn, made the prompt transportation and exchange of commodities essential; indeed, without such a plan, industrial centres could not long exist.
The man whose sole business is manufacture must look to others for his supply of food-stuffs and raw materials, and these are produced more economically at a distance from the centre of manufacture. Thus England must look to the United States for wheat and cotton, to the Australian Commonwealth for wool, and to New Zealand and the United States for meat. Her chief wealth is in her coal and iron, and these make the nation a great manufacturing centre. So, also, the manufacturer of New York must go to Pittsburg for steel, to Minneapolis for flour, and to Chicago for beef.
The application of this principle is very broad; it is the foundation of all commerce, and it underlies modern civilization. For this reason the question of transportation is just as important to a community as the industries of agriculture, mining, and manufacture. Food-stuffs are of no use unless they can be transported to the people who want them; nor can peoples remain in unproductive regions unless the food-stuffs are brought to them.
The gross tonnage of goods is transported mainly in one or another or all of three ways--namely, by animal power, by railway, or by water.
Thus, the cotton-crop of the United States is usually transported by wagon from the plantation to the nearest station or boat-landing; by rail or by barge to the nearest seaport; and by ocean steamship to the foreign seaport.
Water transportation is more economical than land carriage, for the reason that less power is required to move a given tonnage through the water than on the most perfectly graded railway. Steamship freights, as a rule, are lower than those of sailing-vessels, because a steamship has more than twice the speed, and, being larger, can carry a greater tonnage. Freight rates on the Great Lakes are higher per ton-mile than on the ocean, because the vessels are necessarily smaller than those built for ocean traffic. For a similar reason, river and ca.n.a.l freights are higher than lake freights. Railway transportation is economical, partly because a single locomotive will draw an enormous weight of goods, and partly because of the high speed at which the goods move from point to point. Animal transportation is more expensive than any other means ordinarily employed.
=Ocean Transportation.=--In many respects, water-routes form the most available and economical methods of transportation. Intercontinental commerce must be carried on by means of deep-water vessels. Therefore an extraordinary development of ocean carriers has taken place in the past century.
One important period of development began with the rise of American commerce. Just after the close of the War for Independence, it was found that deep-water ships could be built of New England timber for thirty-five dollars per ton, rated tonnage, while a vessel of the same burden built in Europe cost about forty-five dollars per unit of tonnage. Two types of vessels came into use--one, the clipper ship with square sails, was used for long ocean voyages; the other, the schooner, with fore-and-aft rigging, was employed mainly in the coast-trade.
[Ill.u.s.tration: A SQUARE-RIGGED SHIP--A TYPE NOW BEING REPLACED BY FORE-AND-AFT RIGGED SCHOONERS]
In speed and ease of management these vessels surpa.s.sed anything that had ever sailed. In time they became the standards for the sailing-vessels of all the great commercial nations. The types of the vessels are still standards.
[Ill.u.s.tration: THE DEVELOPMENT OF THE MODERN STEAMSHIP]
=The Development of the Steamship.=--Another important era in ocean commerce began when steam was used as a motive power for vessels. The first deep-water vessel thus to be propelled was the Savannah. Her steam-power was merely incidental, however, and her paddle-wheels were unshipped and taken aboard when there was enough wind for sailing. Up to 1860 almost all the ocean steamships were side-wheelers, propelled by low-pressure beam-engines.
The next most important improvement was the screw-blade propeller, placed astern. This means of propulsion called for higher speed of the engines, and in a very short time compactly built high-pressure engines took the place of the low-pressure engine with its heavy walking-beam.
The latter carried steam at a pressure varying from twenty to thirty-two pounds; the modern boiler has steam at 260 pounds per square inch.
Ocean steamships have gradually evolved into two types. The freighter, broad in beam and capacious, is built to carry an enormous amount of freight at a moderate speed. The White Star liner Celtic is a vessel of this cla.s.s; her schedule time between New York and Liverpool is about nine days. The Philadelphia of the American line, though not the fastest steamship, makes the same trip in an average time of five and one-half days.[7]
Twin-screws, instead of a single propeller, are employed on nearly all the large liners. The gain in speed is not greatly increased, but the vessel is far more manageable with two screws than with one; moreover, if one engine breaks down, the vessel can make excellent time with the other.