230 
instance of malted barley, differs from that of the malt, and 
also from the constitution of the barley in its original state. 
The nitrogen of barley in its original state being 
1.3 per cent, or for 1000 prts. carbon, 32 
Malt from the same ...2.1 do. do. do. 50 
Rootlets of maltd. barley 4.3 do. do. do. 106 
So that in the germination of barley there is an increase of 
38 to 50 per cent, upon the original quantity contained in the 
seed ; and this element must be supplied from other sources 
than the seed. It, however, is not only necessary during the 
stage of the first development of plants, but in every after 
stage of their growth ; being most abundant in the early 
periods, and gradually diminishing out of those organs which 
have the most important functions to perform in vegetation. 
But nitrogen, or rather the ammonia from which it is 
derived, performs another most important function in vegeta- 
tion, by carrying into the plant a very considerable portion of 
carbon by the roots ; or in other words, ammonia makes 
available for plants such vegetable substances as simple 
straw, roots of clover, or any other decaying vegetable mat- 
ter in the soil. This, however, is contrary to the received 
opinions of Liebig, Dr. Daubeny, and Professor Johnston. 
The learned Professor, in his third lecture on Agricultural 
Chemistry, says: — " These facts appear to justify the folio w- 
" ing conclusions : — That plants derive their supply of carbon 
'^from the atmosphere^ and that carbonaceous or decoyed vege- 
" table matters accumulate in the soil, because they are not in 
" a condition to minister to the growth of plants. Plants, then, 
''are not necessarily fed by the vegetable matter of the soil. 
" In applying vegetable manure to the land, you do not neces- 
'' sarily add to the soil any portion of carbonaceous matter 
" which you are afterwards to reap in the form of hay^ corn, 
" and straw. Does this appear to be contrary to your pre- 
" conceived opinions ? Has your agricultural experience been 
