532 Observations on Manures , &c. 
iexperb'|ents of Judge Peters, two bushels of gypsum will produce 
a luxuriant crop ; 6 or 8 will prevent it. 
In animals, when parts of muscular or other fibres, are weak, 
diseased and dying, artificial stimuli can be applied to excite an 
action in the living and healthy parts, by which the dead are sepa- 
rated and sloughed off. So in plants, the artificial stimulus of those 
substances which are not manures in the sense of affording nour- 
ishment to the plants, but only as exciting a stronger and more 
healthy action in the living fibre, will kill the weak and diseased 
roots, while they invigorate the more healthy. This is the mode of 
action (in part) of lime, gypsum, salt, See. usually classed among 
manures, but which do not enter into the composition of the plant 
itself. 
Animals are resolveable into gasses, lime and phosphoric acid. 
There is no peculiar animal earth. The phenomena of marine 
animals, the experiments of Vauquelin on the production of lime 
in the hen, and some other facts, make it probable, that the lime of* 
the bones, as well as their phosphoric acid, is the product of annua- 
lization. 
Vegetables are resolveable into gasses and fixed alkali by fire % 
by putrefaction their alkali is either decomposed, or escapes, for no 
fixed alkali is found on the incineration of vegetables which have 
undergone compleatly the putrefactive process. Both vegetables 
and animals contain in their fluids accidentally, unessential quanti- 
ties of iron, manganese, and neutral salts. Thus the blood contains 
iron, albumen, mucilage, the serum, urine, uric and phosphoric 
acids with bases of lime, soda, volatile alkali. So in plants, nitre is 
found in borraee, in nettles, <kc. and oxalates in some. Hence it 
appears, that the essentialy component parts of animals and yege^ 
tables consist chiefly of two or three gasses. 
Again. Animal fibres are made from plants. So true is the 
scripture exclamation that all flesh is grass ! An ox and a sheep 
are made up of vegetables, and so are we who devour them. No- 
thing is nourishment to an animal, but what was originally a vege- 
table. In like manner nothing is nourishment to a vegetable but 
what enters into the permanent composition of a vegetable. We 
find large plants grow in pure sand (Vanhelmont), in sand and 
clay, in common clay, in limestone, in limestone and sand, lime- 
stone and clay, and in all the combinations of these common earths, 
nay even in sulphur, in shot, in pounded glass, but we do not find 
that these earths or either of them, are any permanent and essem 
