Elements of agriculture and vegetation / By George Fordyce, M. D. Fellow Of The Royal College Of Physicians; Physician to St. Thomas's Hospital; and Reader on the Practice of Physic, in London. To which is added an appendix for the use of practical farmers.

  • George Fordyce
Date:
1789
Catalogue details

Licence: Public Domain Mark

Credit: Elements of agriculture and vegetation / By George Fordyce, M. D. Fellow Of The Royal College Of Physicians; Physician to St. Thomas's Hospital; and Reader on the Practice of Physic, in London. To which is added an appendix for the use of practical farmers. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

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    [ 51 ] ' found in Soils are5 Their PROPERTIES. It unites with Acids with great Difficulty. Combined with Vitriolic Acid it forms Allum. It is infoluble in Water. It is always hard enough to ftrike Fire with Steel. It is perfectly infoluble in Water and Acids. Its Powder moiftened with Water, has no Te- nacity, nor does it harden when dried or heated by the Fire. Excepting that they are fofter, and more friable, they agree with Chryftalline Earth in Properties. It is foft and in fine Powder. If it be mixed with water, it forms a tenacious Mafs, which hardens upon drying, and does not diffufe fo readily in Water again as Sand, hard, and burns into a Brick, and refembles in of which it is a Species, only it is much more dif- Difficulty, is of a fmoother Texture and finer Water.