The manures most advantageously applicable to the various sorts of soils, and the causes of their beneficial effect in each particular instance / By Richard Kirwan.

  • Richard Kirwan
Date:
1796
Catalogue details

Licence: Public Domain Mark

Credit: The manures most advantageously applicable to the various sorts of soils, and the causes of their beneficial effect in each particular instance / By Richard Kirwan. Source: Wellcome Collection.

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    / C 32 ] ments adduced to prove it, that of Van Hel- mont, quoted by the illuftrious Mr. Boylef, is by far the moft fpecious. He planted a trunk of willow, weighing 5 lb. in an earthen veffel filled with earth dried in an oven, and then moiftened with rain-water. This veffel, it appears, he funk in the earth, and watered partly with rain-water, and occafionally with diftilled. After five years he found the tree to weigh 169 lb. and the earth in which it was planted, being again dried, to have loft only 2 oz. of its former weight, though the tree re- ceived an increafe amounting to 16,4 lb. Before I proceed to the explication of this experiment, I muft remark fome circumftan- ces attending it: Firft, that the weight of the earth contained in the veffel at the commence- ment and at the end of five years, could not be exactly compared, becaule the fame de- » 1 grees of defecation could not be exactly afeer- tained, and becaule many of the fihrillas of the roots of the tree muft have remained in the earth after the tree was taken out of the veftel, and thefe muft have prevented the true lofs of earth from being perceived. Secondly, That the f 2d Shaw’s Boyle, 240.