146 Report of the Consulting Chemist for 1869. 
Plot. 
1. Quick-lime 10 bushels. 
r, j Quick-lime 10 bushels. 
"'(Common salt 56 lbs. 
3. Fine bone dust Ij cwt. 
^ (Mineial superphosphate 56 lbs. 
■(Crude potash salts 56 lbs. 
5. No manure. 
6. Common salt .. 50 lbs. 
7. Peruvian guano 56 lbs. 
8. Crude potash salts 50 lbs. 
g j Mineral superphosphate 56 lbs. 
(Peruvian guano 56 lbs. 
10. No manure. 
The effect of the manures should be observed for at least four 
successive seasons. The experimental acre should be hurdled 
off from the rest of the pasture-field, and the whole produce be 
carried off and weighed every year, and not be fed off by stock. 
In reviewing the field experiments which, for a number of 
years, I have instituted with special reference to the conditions 
under which the land is benefited by the direct supply of potash 
in the shape of salts of potash, 1 have come to the conclusion, as 
far as my present experience goes, that these salts may often be 
applied with advantage to potatoes, clover, beets, and turnips. 
In several experiments, tried on poor sandy soils during the 
past season, the addition of crude potash salts to superphosphate 
of lime had a very marked and decidedly beneficial effect on 
the potato-crop and also on swedes. Even when applied alone, 
crude potash salts benefit materially root crops growing on poor 
sandy land. The same beneficial effect, I find by direct experi- 
ments, cannot be obtained by the application of common salt, 
showing that soda is a much less valuable fertilising constituent 
than potash, and incapable of replacing the functions of the 
latter in the vegetable economy. 
Hitherto the price of potash has stood in the way of its being 
employed on an extended scale in agriculture. Even in its 
cheapest form — that of crude German potash salts — potash was 
too dear for practical application in agriculture. But as potash 
will, no doubt, be extensively used in agriculture if it can be 
had at a cheap rate, I have pleasure in directing attention to a 
mineral called Kainite, which is found in the neighbourhood of 
Stassfurth, in Saxony, and which, in round numbers, contains 
24 per cent, of sulphate of potash and 12 per cent, of sulphate of 
magnesia. This saline mineral can now be obtained in Eng- 
land in a finely-ground condition, ready for mixing with other 
artificial manures, at about 3/. 3^. per ton, and probably less when 
considerable quantities are required. From 3 to 4 cwts. of ground 
kainite, mixed with an equal quantity of superphosphate of lime 
