in its Relations to Chemistry and Gcohxjij. 
217 
of research, the more refined docs it appear indispens:ible that 
our invesligations should be, and the more practically and ihco- 
retirally useful do such refinements evidently become. 
To some the accuracy in field experiments of which I have 
spoken may seem to be only a speculative good ; but to practical 
men it is in reality a matter of immediate money concern. The 
results of reported experiments guide you in your purchases of 
manuring substances, and have frequently, I have no doubt, led 
some of you to inconvenient loss. 
Second. And this remark naturally leads me to advert to the 
manufacture of artificial manures as one of those circumstances 
which distinctly mark the kind of advancement which scientific 
agriculture has made amongst us of late years, and the position it 
now occupies. 
The possibility of concentrating great fertilizing efficacy in a 
small weight or bulk has been satisfactorily demonstrated to 
every one by the remarkable effects of guano. In watching the 
progress of this branch of science, and marking the obstacles 
which have from time to time stood in its way, it has appeared to 
me as if the finger of Providence might, by serious men, be 
recognised in the introduction of this foreign substance. More 
ccn-n was wanted to feed the growing people, and more manure 
to raise it. More portable and more manageable forms of 
manure also were desired, that it might be applied more fre- 
quently than hitherto, at times hitherto unusual, and in places 
hitherto not easily accessible. How many years of almost un- 
availing labour must teachers of science have spent before they 
could have satisfied the rural communitv, that large bulks of 
manure were, in many cases, unnecessary, and that the success 
of their crops might be trusted to the fertilizing action of any 
mi.xtures they might recommend ! But guano came, and on the 
old principle that " seeing is believing," forced new ideas into 
the oldest heads, and a new belief into the minds of the least 
persuadable farmers. ''I will try some myself next year" was 
the often unexpressed resolution of men convinced against their 
will, and the spirit of experimenting was widely awakened. 
Chemical analysis then took it up, explained the composition of 
guano, declared that it could be imitated at a reasonable rate, and 
published experimental recipes for compounding artificial mix- 
tures to be tried against it. Immediately half-instructed men — 
supposing the practical conclusion already arrived at, which 
more cautious men were only beginning to seek for — hurried 
into what appeared to them a sure and easy way of making 
money. Artificial guanos and prepared manures qualified to do 
everything appeared in the market. The farmer, in many cases 
as credulous now as he was unbelieving before, bought them with 
