BULLETIN OF THE BUSSEY INSTITUTION. T 
No. 2.— On the Amounts of Potash and of Phosphoric Acid 
in several Kinds of Rocks. By F. H. Storer, Professor of 
Agricultural Chemistry. 
F Rom analyses published in the first volume of the Bussey Bulle- 
tin, page 161, note, it appeared that several kinds of rocks occurring 
in the immediate vicinity of Boston, contain so unusually small a 
proportion of potash that it became of interest to determine whether 
the fact was common to all the rocks of this locality, and whether, by 
any possibility, the generality of the rocks of New England were 
equally poor in respect to this constituent. 
In order to test these questions, I have had a considerable number 
of rocks analyzed, with special reference to the amounts of potash 
and phosphoric’acid which they contain. The rocks were from vari- 
ous localities, as will be seen from the table given below; and the 
amounts of potash and phosphoric acid found in them were no less 
varied. This table, it should be said, includes the results previously 
given in Vol. L., p. 161. 
GRANITES. 
Contained per cent of 
A Specimen of: — Potash Phosphoric 
(K,0). Acid (P,0s) 
Coarse feldspathic granite, from the South shore of Hen- 
shaw Pond, Leicester, Mass. . . PL A araaaaen, oe 2, Tt ay a 
Rather fine-grained feldspathic sae tran sf Oak 
Hill,’’ on the border of Lowell, Mass. . . .. . . 5.803 0.060 
Similar to the preceding, and from the same locality . . 5.904 0.058 
Dark-colored, coarse granite, or syenite (?), from a quarry 
in Dracut, Mass., a mile and a half from upper Lowell 
bridge, on the road to Nashua. . . . . 4.263 0.249 
Coarse feldspathic granite, closely Linh ae ae Deiter 
ter sample, obtained at a locality five or six miles dis- 
tant therefrom in the adjacent town of Spencer . . . 4.692 0.084 
Very fine-grained granite from a quarry in Troy, N.H., 
at the base of Mt. Monadnock. . .. . «; » 8.659. 0.112 
Rather coarse granite, carrying a large peeneeare of 
mica, from ledge near new jail at Lowell, on line of 
Boston, Lowell, & Nashua Railroad. .... . . 2.587 0.185 
SYENITES?. 
A specimen from quarry of Eastern Point Granite Com- 
pany, Gloucester, Mass. The sample contained a 
large proportion of feldspar . ... .. . . . 5.804 0.066 
