504 
The Mineral Theory. 
because it is exactly the opposite of organic. As to the term 
mineral constituents, I showed in the 8th chapter of my book that 
the constituents of ashes are originally constituents of minerals — 
thus, potash, a constituent of feldspar ; phosphoric acid, a consti- 
tuent of apatite, &c. — (See also chap. 9, on formation of arable 
soil, and chap. 12, on fallow.) 
From this it will be understood why I used the word mineral 
constituent to designate the constituents of ashes, sometimes of 
soils, but never for ammonia. 
Ammonia is a constituent of the atmosphere, but is never a 
constituent of any mineral : it is mineral and inorganic, but not a 
mineral constituent. 
For a man not versed in scientific language, there is some 
ambiguity in the word mineral — at least in Germany we say sul- 
phate of ammonia is mineral (in its origin), and the mineralogists 
say sulphate of ammonia is not a mineral (species) ; but this has 
nothing to do with Lawes and Gilbert's accusations. 
Although the word organic does not occur in any of the 
sentences epioted from my works, and is never associated with 
ammonia, although I distinctly stated that the opposite of mineral 
constituents was atmospheric, they affirm that by atmospheric I 
understood organic constituents. Their mode of arguing is most 
simple. They take any passage out of my book, twist their own 
erroneous idea into it, and then assert that, by contrasting am- 
monia with mineral constituents, I had regarded it as an organic 
manure. 
The origin of Messrs. Lawes and Gilbert's statements can 
scarcely be understood without referring to a definition of manure 
which Mr. Lawes gave in 1847, and which he is pleased to call 
his theory. It is the following (' Journal of the Royal Agricul- 
tural Society of England,' vol. viii. p. 240) : — ! \ 
"I now come to the action of manures, which are generally divided into 
two classes — organic and inorganic. Although this distinction is by no 
MEANS SATISFACTORY, I SHALL ADOPT IT AS BEING GENERALLY UNDERSTOOD. 
Organic manures are those which are capable of yielding to the plant, by 
decomposition or otherwise, organic matter — carbon, hydrogen, oxygen, and 
nitrogen — constituents which uncultivated plants derive originally 
from the atmosphere. Inorganic manures are those substances which con- 
tain the mineral ingredients, of which the ash of plants is found to consist." 
Before I enter on any discussion of this definition or theory, 
I must beg to recal the views, on the food of plants, which I pub- 
lished in the year 1840. They are contained in the following 
passage : — 
" The elements of nourishment of all green plants are inorganic or mineral 
substances. 
"The plant lives on carbonic acid, ammonia, water, phosphoric acid, sul- 
