Agricultural Chemistry. 
415 
occurs in the original, but is not given by Baron Liebig in his 
apparently continuous quotation from our Paper. 
"In the course of this inquiry, the whole tenor of our results, \_anil also of 
information derived from intelligent a<jricnltu,ral friends, vpon every variety 
of land ill Great Britain'], has forced upon us opiuions different from those of 
Professor Liebig on some important points ; and more especially in relation to 
his so-called ' mineral theory,' ^yhich is embodied in the following sentence, 
to be foimd at page 211 of the third edition of his work on Agricultural 
Chemistry, where he saj-s, ' The crops on a field diminish or increase in exact 
proportion to the diminution or increase of the Biineral substances conveyed 
to it in manure.'" — Journal of ih.e Boijal Agricultural Society of England, 
vol. xii. part i. p. 2. 
With regard to the omission made by Baron Liebig in his quo- 
tation, we will only here observe how important is such an omis- 
sion, when one of the main objections which Baron Liebig alleges 
against our conclusions is, that they are fomided upon our own 
experiments alone, and without any consideration of what would 
happen on other soils and in other localities ! 
Baron Liebig also complains that the sentence which we 
have quoted as embodying his own doctrines, has been de- 
tached from its natural connection with a series of sentences, 
and thus a meaning given to it quite different from that in- 
tended by its author. In proof of this, he gives the sentence in 
question with its context, and also comments, to which we shall 
call attention. But here we must once more beg the notice of 
the reader to Baron Liebig's inaccurate mode of giving a quotation 
for the purposes of controversy, within unbroken inverted commas. 
AVe give the sentence, from p. 210 of the 4th edition of Baron 
Liebig's ' Chemistry in its Applications to Agricultwe and 
Physiology^ from which he himself professes to quote. The 
two first portions which we give between brackets, thus [ J, 
occur in the original, but are omitted in Baron Liebig's quotation ; 
and the word " the " so inclosed is given in the quotation, but 
does not occur in the original : — 
" Hence it is quite certain, that in our fields, the amount of nitrogen in the 
crops is not at all in proportion to the quantity supplied in the manure, and 
that \thc soil cannot he exhausted hy the exportation of products containing 
nitrogen (^unless these p/roducts contain at the same time a large amount of 
mineral ingredients'), because the nitrogen of vegetation is furnished ly the 
atmosphere and not hy the soil. Hence alsci] we cannot augment the fertility 
of our fields [or their p)owers of p)roduction\ by supplying them with manures 
rich in nitrogen, or with ammoniacal salts alone. The crops on a field 
diminish or increase in exact proportion to the diminution or increase of the 
mineral substances conveyed to it in [thel manure.'''' 
The reader will perceive more clearly as we proceed, the 
importance of the omissions made in the quotation of the 
above sentence, bearing, as they do, both upon the question of 
what were Baron Liebig's opinions as to the dependence of 
2 E 2 
