390 BULLETIN OF THE BUSSEY INSTITUTION, 
that are given in the third column of the table. For the sake of con- 
trast, I have given in the fourth column the number of pounds of salts 
soluble in water, or “crude potashes” that were obtained from each 
of my samples of ashes. These figures represent the amounts of solid 
matter that were obtained on evaporating measured quantities of the 
lyes and igniting the dry residues ; they are comparable with most of 
the figures in column six of the table on pages 207-245. 
It has been shown already, on page 387, that the alkali-power of the 
ashes from husk of cotton seed was found to be 12.290, in terms of 
pure carbonate of potash; that is to say, about the same as that of 
several of the best samples of wood-ashes. ‘The alkali-power of the 
New Bedford prussiate residue was high; namely, 51%. This sub- 
stance is doubtless well adapted for making compost, as has been 
already suggested. 
It is no very easy matter to determine the precise money value to 
the farmer of the alkali-power of ashes. In the lack of more definite 
means of information, and taking, one year with another, perhaps as 
fair a way as any of arriving at an approximate valuation would be to 
credit the ashes with the cost of as much soda ash as would represent 
the alkali in the ashes. ‘Thus, at the present time (November, 1870), 
soda ash containing 80% of pure carbonate of soda is quoted at three 
cents (currency) per pound in Boston; and, in order to get as much 
alkali in this form as would be equivalent to the 10 pounds of carbonate 
of potash which may be assumed to be contained on the average in 
100 pounds of wood-ashes, 94 pounds of the soda ash would be needed. 
Hence the sum of 2 cents, which this amount of soda ash would cost, 
may be taken as the alkali value of the 100 pounds of wood-ashes ; 
and each pound of the carbonate of potash in the ashes may be esti- 
mated to be worth $0.29 — 10 = $0.029 ; that is to say, nearly three 
cents, on account of its alkalinity alone. But since house ashes are 
held to weigh 48 pounds to the bushel, on the average, the alkali-worth 
of a bushel of ashes, as prices now go, may be said to be about 14 
cents. Now, from the averages of the analyses that have been given 
on page 193, it appears that ashes contain about 83% of real potash 
and about 2% of phosphoric acid; and, if we allow five cents per 
pound for the potash and six cents per pound for the phosphoric 
acid, there will be 26 cents per bushel to be added to the alkali- 
worth (14 cents) that was just now given. Whence it appears that 
