278 Commercial Value of Artificial Manures. 
they likewise afford important data in estimating the money 
value of manures. 
But the gigantic dimensions which the manufacture of arti- 
ficial manures has assumed during the past few years in this 
country, and the consequent altered conditions of the manure 
trade, necessitate not only several modifications in the prices at 
which the various constituents of artificials are valued, but like- 
wise much circumspection in estimating by analysis and calcula- 
tion the money value of a manure. 
Having, in my capacity of Consulting Chemist to the Royal 
Agricultural Society, numerous samples of all kinds of artificial 
manures annually submitted to me for examination and opinion, 
and having, moreover, made myself practically acquainted with 
the manufacture of artificial manures, and attentively followed 
its rise and progress, I believe that I am in a position to say 
without hesitation that the true money value of a manure cannot 
always be calculated with anything like precision by mere 
reference to an analysis and certain valuation-tables. I feel in- 
clined to go a step further, and maintain that, at the present 
time, such mere rule-of-three calculations frequently convey 
wrong impressions of the value of certain manures, and do not 
further the real interest of the consumer. In proof of this I may 
state that, not long ago, I saw a copy of an analysis of a manure, 
the commercial value of which, estimated according to the usual 
tables, was given at 11/. 10s. a ton, and yet this article was 
offered for sale at 11. 10s. a ton. It may, perhaps, be presumed 
that this manure is manufactured under peculiarly favourable 
circumstances ; but this is not an exceptional case, for the calcu- 
lated value of certain superphosphates rich in soluble phosphate 
of lime is generally 21. or 3Z. higher than the price at which 
they are actually sold. On the other hand, it is no unusual 
occurrence to meet with really good and cheap fertilisers, which, 
submitted to ordinary commercial analysis, give apparently un- 
satisfactory results, inasmuch as their value, when calculated 
according to any of the approved tables, is set 1?. to 21. lower 
than their true money value. Recent experience has convinced 
me that the buyer may now justly expect something more in a 
manure than the mere agreement of its calculated value with the 
price at which it is actually sold. It is, comparatively speaking, 
easy to prepare a manure say at 6/. a ton, the calculated value of 
which amounts to the same sum ; but such agreement, in my 
opinion, is no guarantee that the manure is really worth that 
price. It is well known to all acquainted with the peculiarities 
of the trade in artificials that many samples which, as the saying 
is amongst manufacturers, " analyse well," can be produced at a 
