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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    [ 4+ ] torn grew in them profperoufly *. Hence the neceffity of the carbonic principle is apparent. The abfolute quantity of earth in vegetables is very fmall. Dr. Watfon informs us that 106 avoirdupois pounds 1696 ozs. of oak, being carefully burned, left but 19 ozs. of allies ; and from thefe we muft deduft 1,5 for Tilt, then the earthy part amounts only to 17,5; that is, little more than one per cwt. The commiffioners appointed to infpect the faltpetre manufadtory, found nearly the fame refult; namely, 1,2 per cwt. in beech 0,453, # and in fir only 0,003. Hence we need not wonder at trees growing among rocks where fcarce any earth is to be feen; but in the ftalks of Turkey-wheat, or maize, they found 7 per cwt. of earth, in fun flower plant 3,71; fo that, upon the whole, weeds and culmiferous plants contain more earth than trees do. Mr. Weftrumb found trifolium pratenfe to contain about 4,7 per cwt. of earth, of which 2 per cwt. was mild calx, nearly 2 more filex, 0,7 argill, together with a fmall proportion of phofpho- J Encyclop. Vegetation, 274.