in its Relations to Chcmidnj and Gcolo{jij. 
22o 
cautions; but wc are thankful for them as tlicy are. They have 
prepared the way for more unexceptionable results, and have in- 
dicated new lines of research and new fields of inquiry. Tiiey 
have suagested new questions to be asked of Nature, and, like all 
real advances in knowledge, instead of in any way completing 
the branch of science they elucidate, they have only made the 
nakedness of the country more apparent, and widened the horizon 
we have 3 et to explore. 
And while on this subject I ought not to pass without especial 
notice the labour that has been successfully expended upon this 
department in our own island through the instrumentality of this 
Society, and of the two Societies in Scotland, within whose pro- 
vince it more or less particularly comes. For several years this 
Society (The Royal Agricultural Society of England) has devoted 
an annual sum to the examination of the ashes of plants — a wide 
but definite field in which Professor Way has been induced to 
labour, and whose valuable contributions to our knowledge upon 
this subject are recorded in the later parts of the Society's 
Journal. I trust the Council will not grudge the means of con- 
tinuing these and similar analytical inquiries, and that the office 
now held by Mr. Way in connexion with the new English Agri- 
cultural Chemistry Association will place still more facilities in 
his hands for cultivating the less popularly understood depart- 
ments of this branch of science.* 
* In an interesting paper by the Messrs. Rogers, of the United States, 
on the action of carbonic acid in decomposing mineral substances, lately 
published in Silliman's Journal, May, 1848. The authors conclude with 
the following passage : — 
" From the great rapidity with which, according to our experiments, 
potash and soda and their carbonates, but especially potash and its car- 
bonate, rise in vapour, at a strong red heat, we are persuaded that a large 
error must be committed in estimating the amount of these materials con- 
tained in plants by the results of incineration ; and we believe that in not 
a few eases the quantity obtained is scarcely one half of what really exists 
in the vegetable mass. The important bearing of this consideration upon 
the late numerous and elaborate analyses of ashes should, we think, claim 
the special attention of chemists. Indeed, it seems a little remarkable tliat 
the source of error here referred to has not already been brought to the 
notice of analysts, as likely to modify materially their results." I think it 
right to notice this paragraph for the purpose of adding a word in behalf of 
our English analyses. The remarks of the Messrs. Rogers are certainly 
applicable to the Giessen method of inirning vegetable substances in Hes- 
sian crucibles; but I am not aware that any respectable chemist in Britain 
either advocates or follows so rude a method. For ten years that ash de- 
terminations and analyses have been made in my laboratory, vegetable sub- 
stances have invariably been burned in the open air at a low, scarcely a 
red, heat over a gas lamp, usually in open platinum capsules, and only 
rarely in crucibles. Any one who considers for a moment that alkaline 
chlorides occur in the ashes of plants, and how easily these, and espe- 
cially common salt, are volatilized, will see that no ash, which is not pre- 
pared at a low temperature, can be expected to contain all the alkaline 
VOL. IX. Q 
