50 BULLETIN OF THE BUSSEY INSTITUTION. 
No. 4.— On the Agricultural Value of the Ashes of Anthracite. 
By F. H. Srorer, Professor of Agricultural Chemistry. 
The question “whether the ashes of hard coal have any fertilizing 
power ” has often been debated in New England. 
It is a not unnatural assumption that coal-ashes should have some 
value as manure, in view of their analogy with wood-ashes, and of the 
current belief that coal has been derived, if not from wood; at least 
from plants of some kind. But coal is a substance that has under- 
gone many changes, and we have to consider, not only what propor- 
tion of the potash and phosphoric acid originally contained inethe 
coal-producing vegetation has been left in the coal, but how much of 
the potash and phosphoric acid in a coal is left in the ash of that coal 
in a condition fit for the use of growing plants. In other words, we 
must inguire how much of the original potash and phosphoric acid 
have been washed out by water while the coal was being formed, or 
have been locked up and compounded by the action of heat, — either 
the heat to which the coal may have been subjected while forming, or 
that which it must necessarily undergo when burned. 
Several attempts to answer the main question, in part at least, have 
been made by way of analyzing the coal-ashes.* But in the present 
imperfect condition of chemical art we can hardly hope to determine 
by analysis alone what portion of the potash and phosphoric acid 
actually found in coal-ashes is fit and ready to serve as plant-food. On 
the other hand, very many farmers ‘and gardeners have tried to esti- 
mate the value of coal-ash by noting its action upon crops in actual 
field practice, and it is with regard to the results of these tests that 
discussions have arisen in our agricultural societies. In point of fact, 
it is not easy to come to any very nice or very definite conclusion in 
this way ; the experiment is necessarily complicated by bringing the 
ashes into the presence of a great variety of substances, — both those 
natural to the soil and those which have been added to it by previous 
manuring, — and unless the ashes possessed decided and well-marked 
fertilizing power it. might often happen that they could not exhibit 
* See, for example, Bunce, ‘“ Wells’s Annual Scientific Discovery,”’ 1851, p. 305; 
Horsford} “ Proceedings American Scientific Association,” 1849, p. 233. 
