determine either generally, or in particular cases, the precise point at which agriculture should stop, to prevent relatively smaller returns from increased expenditure of labor and capital. Improvements in the art of agriculture may remove it a great distance. But, that there is such a point admits of no doubt. No one will believe that an acre of land can be made to produce a quantity of the means of subsistence sufficient to support all Europe, no matter what the amount of seed used, or of manure etc. employed. This is most apparent in foresteconomy, where the absolute increase of the so-called woodcapital becomes, after a certain time, smaller from year to year.3 lently stretched, that it could not possibly be stretched any more, yet the pressure of which is felt long before the final limit is reached, and felt more severely the nearer that limit is approached." This is, if possible, more obvious in building than in agriculture, both as to the construction of new stories and the excavation of deeper cellars. Ad. Mayer, Das Düngerkapital und der Raubbau (Heidelberg, 1869), sees the only conditions of production which man cannot increase at will exclusively in the sun's rays, the employment of which also depends on the quantity of land. Thus would he explain Senior's law. See the tables of increase in Cotta, Anweisung zum Waldbau, p. 228. Count Buquoy, Theorie der N. Wirthschaft, p. 54, ridicules the absurd procedure of a great many farmers, as if by forcing the ploughshare deeper into the soil, they could compel it to produce a double return, and asks: if one should dig a square foot of land to the center of the earth and manure it, who would take it off his hands? As to the effect of manure, Kuhlmann's investigations have shown that 300 kilogrammes of guano produced in three years an increase per hectare in the yield, of 2,469 kilogrammes of hay; while 600 kilogrammes produced an increase of only 2,870 kilogrammes. Schübler, found that where salt had been used for manuring purposes, 40 kilogrammes produced a maximum of fertility from which point forward every increase in the amount of salt was attended by diminished returns, and finally led to complete barrenness. See Wolff, Naturgesetzliche Grundlagen, I, 408, 412, 502. Constantly increased irrigation would convert the land into a swamp instead of indefinitely adding to its fertility. Nor can abundant sowing be of any use when it reaches such a point that the plants stand so closely together as to interfere with their proper development. VOL. I. - 9 SECTION XXXV. Т EXTERNAL NATURE. - ELEMENTS OF AGRICULURAL PRODUCTIVENESS. In treating of the agricultural productiveness of a piece of land, it is necessary to distinguish three things, its bearingcapacity, its capacity for cultivation, and its direct capacity to afford food to plants. Plants grow by drawing a part of the elements which enter into their composition from the atmosphere, and a part from the earth through the agencies of sunlight and of water. While the air, the sun's heat, and in most parts of the world, water, are free and inexhaustible goods, the earth's supply of food for plants must be considered as analogous, so far as its exhaustibility and capacity to be appropriated are concerned, to the beds of coal and of ore etc. which occur in mining districts. This is certainly true, with a few important differences, however, as for instance, that, as a rule, it is impossible, except through the cultivation of plants, to obtain from the earth the stores of plant food which it contains;2 and that it is possible to husbandry to replace the portion of these stores taken from the earth by the harvest, through the agency of manures. Incomparably more important in the economic valuation of a piece of land is its capacity for cultivation, because this de 'These differences correspond with the differences in the kinds of deterioration to which land is liable from rivers, floods, lava, etc., soil-exhaustion, and the growing wild of the land. 2 From a technic point of view, it would, perhaps, be practicable, in most instances, to obtain the phosphoric acid immediately from the land and transfer it to other land; but the relation of the cost to the result makes it impossible from an economical point of view. 3 It most certainly is always an uncommon advantage that certain kinds of soil, rich in kali and decayed vegetable matter, yield a long series of harvests without the addition of manure, provided, always, that a short interval is allowed to the process of decay to replace the exhausted plant-food. Thus in many volcanic regions. Compare on similar districts in the Deccan: Ritter, Erdkunde, V, 714. pends much less on the good or bad quality of the husbandman's art. I mean here the so-called physical constitution of of the vegetable soil; its water-holding power, its consistency (light or heavy soil) on which the difficulty of working it depends; its ability to dry, in a shorter or longer time, and its accompanying diminution in volume; its ability to draw moisture from the atmosphere and to absorb the various kinds of gases; its heat-absorbing and heat-containing power (hot, warm and cold soils). Much depends here on the depth of the vegetable soil and on the constitution of the sub-soil, which, for instance, when it is very permeable, improves a very moist soil, but in the form of meadow iron-ore (Wiesenerz), works great injury. The vertical form of the land is also a very important element in estimating the natural fertility of the soil. In mountainous districts, the quantity of land which can be used (and with what labor!) is wont to be relatively smaller than in low lands. Hence it is, that the former become too small for their inhabitants; who, therefore, swarm over the plains lying before them either as settlers or conquerors. In the eastern hemisphere, the northern slopes According to Schübler, the absorption of water by 100 parts of earth is, in the case of quartz-sand, 25 per cent. of its weight; for clay, 70 per cent.; for calcareous earth, 85 per cent.; humus, 190 per cent.; and for 100 parts of their value, respectively, 37.9, 66.2, and 69.2 per cent. The consistency of the four kinds of earth, in a dry state, is in the proportion of 0.100, 5, 8.7; their adhesion in a moist state, to iron agricultural implements, is in that of 0.17, 1.12, 0.65, 0.40. Of 100 parts of water mixed with these kinds of earth, the evaporation in four hours, at a temperature of 18° 75' (centigrade) is 88.4, 31.3, 28 and 20.5 per cent. respectively. The diminution of volume when the moist earth dries, under the same degree of temperature, is, o, 18.3, 5 and 20. Their relative absorption of atmospheric moisture for 48 hours is as o, 24, 17.5 and 55; their absorption of oxygen in 30 day's is respectively 1.6, 15.3, 10.8 and 2.03 per cent.; and, lastly, their heat-holding power is in the ratio of 95.6, 66.7, 61.8, 49. 5 In Austria, below the Enns, only 3.8 per cent. of the soil is barren; in the Tyrol, 29 per cent.; in Dalmatia, 48.1 per cent. (Springer). In the French Pyrenees, 43 per cent. is considered incapable of cultivation; in the Alps, in Landes and Morbihan, 42 per cent.; in the departments of Nerd and Somme, 1.3 per cent. (Schnitzler). Franscini considers 36 per cent. of Switzerland of mountain regions are most unfavorably situated, although the southern slopes are frequently subjected to more trying and more sudden variations of thawing and freezing weather. But all these more special qualities of the soil must be distinguished from their general basis, the bearing or carrying capacity which land possesses as a mere superficies, and which the most naked rock (Malta!), and the bed of a flowing stream (the floating gardens of China!) possess to some extent, since there is a possibility of establishing a plant-feeding surface on them. This bearing capacity, which in most instances is given only by nature, and which can be added to only to a very limited extent and at great outlay, is wont, when the population is very dense, to acquire considerable exchange value in the vicinity.78 unfit for tillage. The idea "barren" is a very vague one, and hence a comparison of different countries on this point should not be made without great caution. 6 Wolff, loc. cit., 353 ff. As to the manner in which soil and climate mutually improve or injure one another, see Schwerz, Prackt. Ackerbau I, 12. In this respect, also, the fundamental difference between agriculture and industry is very important, inasmuch as the products of the former, equal in value to those of the latter, require a very large supporting or bearing surface; those of industry, a very small one. If Nobbe's "water-cultivation " should ever come to assume any great practical importance, agriculture would approach to industry in this respect. 8 Wolkoff has called special attention to mere emplacement: Lectures d'Economie politique rationelle (1861), pp. 90 seq., 157 seq. Bastiat's rather broad and enthusiastic assertion, that no mere product of nature possesses value (in contradistinction to utility), an exaggeration of his very honorable contest with the socialists (1848!), is refuted by daily experience, as when, for instance, discoveries are made accidentally of metallic veins, coal-fields etc., which immediately acquire great exchange value. SECTION XXXVI. EXTERNAL NATURE.-FURTHER DIVISIONS OF NATURE'S GIFTS. The gifts of nature, we further divide into those which can be directly enjoyed and those which are of use only indirectly, by facilitating production. (Natural means of enjoyment,—— means of acquisition.) An extreme superfluity of the former is as disastrous to civilization as a too great scarcity of them. How simple the economy of a tropical country! A banana field will support twenty-five times as many men as a wheat field (K. Ritter); and with infinitely less labor; for all that is needed is to cut the stems with their ripened fruit, to loosen the earth a little and very superficially, when new stems shoot up. At the base of the mountains of Mexico, a father needs labor only two days in the week to support his family. Hence, nothing so much excites the wonder of the traveler there as the diminutiveness of the cultivated ground surrounding each Indian hut. But in these earthly paradises, 1 Aristotle distinguishes between απολαυστικὰ and κάρπιμα. (Rhet., I, 5.) Humboldt, Essai politique, sur la N. Espagne, IV, 9, in which he estimates the relation of the culture of the banana to that of wheat, in respect of mere quantity, to be as 4,000 to 30,-"probably the best gift of nature to awakening man, and the object of the most ancient cultivation." "It was said that in Easter Island, three days' labor sufficed for a man's maintenance through the whole year. A similar gift of nature to tropical lands is the date tree. It is turned to so many different uses that the Arabs of the coast of the Persian Gulf say that it is possible to construct a ship, rig it, supply and freight it, from date trees. Houses are built of palm wood, covered with palm leaves, furnished with palm mats, lighted with palm chips, and heated with palm coals. The whole architecture of these countries is fashioned by the date tree. Date wine is the favorite intoxicating beverage. There is a proverb current there that a good housewife can vary the preparation of the date for her guests every day in the month. Even the pulp is eaten. Each tree yields an average of 50–250 lbs. of dates; and a tree may last over 200 years. An acre may contain more than 200 trees. The labor of cultivation is very slight, although it demands more care than the banana. Compare Ritter, Erdkunde, XII, 763. An acre planted with the sago-palm yields |