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out this as a possible result of a new system of agriculture, that vegetable products will be found well suited both for the climate, as regards profit to the farmer, and to the health of the inhabitants, who, under the present artificial inducements to the rearing of cattle, and consequent cheapness of meat, eat a great deal too much of it, and neglect those more salutary productions which nature provides as the cheapest and best food for a dense population, many of whom are occupied in sedentary employments quite inconsistent with a stimulating diet. We see, then, that the adoption of Liebig's views will ultimately prove beneficial to the country in several ways. First, by increasing the fertility of land; second, by diminishing disease; and thirdly, by rendering the nation independent of foreigners for food. It is also no small matter to be able to purify our streams, if we only consider them as the source from which all urban populations are supplied with the water which they drink. There will, no doubt, be some difficulties in the details of every new principle when it comes to be applied, but I have no doubt that it will make its way gradually, and ultimately be taken into consideration by the legislature.
As, no doubt, all sorts of objections will be advanced against the adoption of any principle which tends to interfere with vested interests, it may be as well to notice in anticipation those which will have the greatest appearance of plausibility. That which will operate most powerfully in blinding people's eyes will be the appeal to experience in favour of the existing state of things. In the words of Liebig—"So long as agriculturists derive from the spoliation of their own lands plentiful crops and a good income, there is no hope of the advent of a more rational system of husbandry. The field is to such men simply a cow that gives them milk, but which they would feed with its own flesh taken from its ribs; and the folly of such a proceeding would strike them only when the light shines through the hollow skeleton of their victim." "In the flesh and the produce of the field, we have for centuries supplied to the large towns the constituent elements of guano, and have never brought this guano back again, and we now send vessels to Chili, Peru, and Africa for this substance. By the exportation of these elements our fields have lost in productiveness: were it not so, how could it have been conceivable or possible for us to raise their fertility by the importation of these elements? Agriculturists must not rely on guano; its price at the present time, as compared with an earlier period, is already doubled, and no sensible man would entertain the idea of making the production of an entire country dependent on the supply of foreign manure." Liebig further shows that not only does guano exert a powerful influence upon the soil, by restoring the elements of which it has been spoliated, but that all its good qualities are possessed by human excrements, in addition to others which it is deficient in. He says:—"The excrements of man contain the full complement of mineral elements removed in flesh and grain, but in guano there is wanting a certain quantity of potash to replace fully these ash constituents. Hence, on soils poor in potash (on lime and sandy soils), the action of guano after a certain time percep-
