[167] Recent experiments by Müntz and Girard in France have shown that the loss in sheep excreta from volatilisation of the carbonate of ammonia amounted to over 50 per cent. By the use of straw litter this was reduced to about a half less, and with earth litter one quarter less.
[168] See Appendix, Note XIII., p. 288.
[169] See Appendix, Note XIV., p. 289.
[170] See Appendix, Note XV., p. 290.
[171] For spring application rotten farmyard manure is generally used, because in this condition its fertilising matter is more quickly available. On light land it is best to apply it in the rotten condition shortly before it is likely to be used. (See p. 261.)
[172] The total amount of plant-food in a ton of farmyard manure is together less than 1/20th of its total weight.
[173] See Heiden's 'Düngerlehre,' vol. ii. p. 171.
[174] For full details see Appendix, Note XVI., p. 290.
[175] Storer reproduces these results in his 'Agricultural Chemistry,' vol. ii. p. 21.
[176] This aspect of farmyard manure has been ably stated by Mr F. J. Cooke, a well-known Norfolk farmer. In commenting on the results of the Rothamsted experiments, he says: "It is clear enough that the faith of the farmer in the soil-enriching character of his home-made manure is amply justified; the only question being, indeed, if this quality be not too highly appreciated. It is not, after all, so much by the fattening of our land as by the bounty of the crop grown upon it that we reap the fruit of our exertions. The man of scientific mind keeps his purpose fixed on the production of good crops mainly, and the cheapest way to grow them. The experiments under consideration show that richness of land may be purchased much too dearly, and that richness of crop by no means bears the necessary relation to richness of soil which has sometimes been imagined. We may boast of the 'lasting qualities' of our dung, but the answer of science by these experiments is, that so great is the last that the life of one man may not be long enough to exhaust it. In the extravagant use of dung, therefore, such considerations, amongst many others, as length of purse, as well as length and character of tenure, must clearly be taken into account."