Art. V.~ ?The Natural Laws of Husbandry. By Justus von Liebig.

ColWpkp ^LYTH> M.D., Professor of Chemistry in Queen's

College, Cork. London, 1863. pp.416.

a^riculturp to tIle ^esiou ?f our Review

to notice works on

o > are for once tempted to make an exception in favour

150 Bibliographical Record. [Jan.

of Baron Liebig, to whom we are so deeply indebted for the chemical science which he has brought to bear on the most important of the arts?which agriculture surely is?for the instruction he gives to the farmer, and also for his warnings to the statesman and the landed proprietor.

Though few members of the medical profession engage in agricul- ture, yet most of them have, or should have, as physiologists, a know- ledge of its principles ; and as they are daily in habits of intercourse with farmers, they have ample opportunities of calling attention to bad practices and to modern improvements in husbandry.

It is not our intention now to review this admirable work of Baron

Liebig, but chiefly to impress on our readers one of the great defects of agriculture?as it is generally conducted in Europe?that of the exhaustion-practice; that of taking from the land in over-cropping more than is returned to it, from undermanuring, as if the earth, 'per se, were inexhaustible, and tillage could be made in perpetuo a substitute for manure.

Liebig throughout his work raises his voice against this mal-practice, and powerfully descants on its impoverishing evils. The impoverish- ment he deprecates is the loss of the fertilizing elements belonging to the soil essential to vegetation, varying according to the nature of the crop, and not the gaseous elements derived from the atmosphera If the former are not returned in the same pi'oportion as they are ex- tracted, he demonstrates that the land eventually must become barren. Happily he is able to illustrate his views on this subject by an account which is given in the appendix to his book of the Japanese system of husbandry, extracted from a Report to the Minister of Agriculture in Berlin, by Dr. H. Maron, Member of the Prussian East Asiatic Expe- dition. That system is singularly contrasted with the modern European system, and in accordance with the Baron's mature scientific views. The

Japanese farmer is described as master of his land, mastering it by a drill method of husbandry, by the manuring of every crop, and by the careful preservation of human excrement. Eallows are unknown

to him. He imports no foreign manure ; he stands in need of no foreign supplies of grain. The land is made self-supporting ; and yet the country has a population exceeding proportionately that of Great Britain and Ireland. And why is this 1 It is because the income

and expenditure of the soil are always kept evenly balanced, the farmer carefully avoiding the impairing the productive power of the virgin land, never breaking up a plot unless he possesses a stock of manure which he may invest in the ground.

All the details?and they are minutely given?of this excellent

agriculture, by Dr. Maron, are deserving of being read and re-read, and of being treasured up in the memory of the farmer. We cannot but

feel surprised in perusing them that the art of husbandry should have been brought to such a pitch of excellence without the aid of chemical science, merely by the common sense of an acute people taught by experience. We shall give one passage?that descriptive of the Japanese privies,

1864.] Liebig on the Natural Laws of Husbandry. -i51

oil which their husbandry mainly depends for manure, and the pre- vention of that exhaustion which threatens our fields.

" The Japanese does not construct his privy as we do in Germany in some remote corner of the yard with half open rear giving free admission to wind and rain, but he makes it an essential part of the interior of his dwelling. As he

ignores altogether the notion of a ' seat,' the cabinet, which, as a general rule, is very clean, neat, and in many cases nicely papered, or painted and varnished, has a simple hole of the shape of an oblong square, running across and opposite to the entrance door, and serving to convey the excrement into the lower space. Squatting over this hole, with his legs astride, the Japanese satisfies the call of nature with the greatest cleanliness. I never saw a dirty cabinet in Japan, even in the dwelling of the very poorest peasant. We in Germany construct privies over dung-holes, and behind our barns, for the use of our farm-servants and labourers, and provide them with seats with round holes. With even only one aperture, it is too often found that after a few days' use they look more like pig-styes than closets for the use of man, and this simply because our labourers have a decided, perhaps natural, predilection for squatting. The con- struction of the Japanese privies shows how easy it would be to satisfy this predilection.*

" To receive the excrements, there is placed below the square hole a bucket or tub, of a size corresponding to it, with projecting ears, through which a pole can be passed to carry the vessel. In many instances a large earthen pot, with handles, is used, for the manufacture of which the Japanese clay supplies an excellent material. In some rare instances, in the town, I found a layer of chopped straw or chaff at the bottom of the vessel. As soon as the vessel is

full, it is taken out and emptied into one of the larger dung-vessels. These are placed either in the yard or in the field. They are large casks or enormous stoneware jars, in capacity from eight to twelve cubic feet, let into the ground nearly to the brim. It is in these vessels that the manure is prepared for the field. The excrements are diluted with water, no other addition of any kind being made to them, and stirred until the entire mass is worked into a most intimately intermixed pap."

Further particulars are given respecting the fermentation of the manure : it is especially mentioned that under no circumstances is it

ever used in the fresh state, leaving the ammonia exposed to decomposi- tion by the action of the sun and its volatilization by the wind, but taking the greater care to shield the solid ingredients from being washed or swept away by rain, &c. Now, could this valuable manure be protected from waste, applied

to our fields instead of being allowed, owing to our fastidious water- closet plan, to flow into our streams and pollute their water, how vast would be the gain; millions would be saved at present expended on the importation of guano and bones, and that exhaustion of the soil which is threatened, and is, without change of system, as certain as the final exhaustion of our coal-fields, would be arrested. As has been well observed by the father of agricultural chemistry, Sir H. Davy, when treating of this kind of manure, that " that which would offend the senses and injure the health if exposed, is converted by gradual pro- cesses into forms of beauty and usefulness; the fetid gas is rendered

a

. ^ *s a Predilection, we may remark, can hardly be doubted; in Turkey

and Asia Minor the privies are of the same kind as in Japan, though not with a view to agricultural profit, and also in the Eastern world generally.

152 Bibliographical Record. ? [Jan.

constituent of the aroma of the flower, and what might be a poison becomes nourishment to animals and man."