306) BULLETIN OF THE BUSSEY INSTITUTION, 
cost of the ingredients of such mixtures as compared with that of the 
dung of animals. In respect to the barley crops, for example, a glance 
at the column headed “ Weights of barley grain” in the Table of Best 
and. Worst Crops on page 305, shows that. almost every one of the mix- 
tures of a nitrogenous, a potassic, and. a phosphoric fertilizer that were. 
employed yielded useful results, as compared with those obtained from: 
barn-yard or stable manure applied at the rate of ten cords to the acre. 
See beyond page 315, for the results obtained with cow dung and 
horse dung in 1874, and the general table on page 164 for the results 
of previous years, squares B 1, and B 2. 
A very simple calculation will be sufficient to give an idea of the 
small cost of employing the mixed fertilizers, as compared with the 
cost of buying farm or stable manure. Let us take for example 
the mixture that was applied to square EE 2, which gave the best 
yield of barley grain in 1874. The crop. was at the rate of 3974; 
bushels to the acre. Since each of the squares was equal to +}, of 
an acre, there would be needed of the mixture in question for an acre 
of land: — 
Of nitrate of soda . . 1139 grms. X 162 = 184.510 kilos. = 406 Ibs. 
Of sulphate of potash. 463 ,, »% 162= 75.000 kilos. —165 ,, 
Of Coe’s superphosphate 714 ,, > 162 = 115.670 kilos. = 2543 ,, 
But in the spring of 1874 nitrate of soda could be bought at the 
rate of 3} cents per lb., currency; sulphate of potash, containing 54% 
of real potash, could be bought for less than 3 cents per lb.; and the 
price of Coe’s superphosphate was $50, per ton: whence it appears that 
_the cost per acre of the mixture in question would have been : — 
406 lbs. nitrate of soda. . «0, wo o  « @$0,0875 = $15.25 
165. ,, sulphate of potash . . » - . , «+ (@). U.Og sme 
255 ,, Coe’s superphosphate. . . . . « . @ 0.025 = 6.38 
$26.56 
I have taken the above mixture at random for this discussion, 
merely because the barley crop obtained by means. of it happened to 
stand at the head of the list.. The mixture is not one to be specially 
commended. On the contrary, the amount of nitrate of soda contained 
in it might undoubtedly be reduced at least one-half with advantage. 
But it is manifest that the prime cost of the mixture, taken exactly as 
it was.used, will compare fayorably with that of ten cords of farm or 
