Annual Report for 1891 oj the Consulting Chemist. 843 
manures for the purpose of diluting them, or for spreading on grass- 
land. Of course it would not bear the cost of carriage to any 
distance. 
Cutlers' Dust. — A sample of this, obtained from Rotherham, gave 
on analysis : — 
Moisture ......... o'94 
■ Organic matter ........ 34 46 
Phosphate of lime 10 64 
Carbonate of lime ....... 4 86 
Metallic iron 22-95 
Sand 2115 
100-00 
' Containing nitrogen .... 2-46 
Equal to ammonia ..... 2-98 
31. \5s. a ton, delivered, was the price asked for this, one which is 
decidedly above its value. 
Sulphate, of Copper. — In connection with the experiments con- 
ducted by the Society on the efficacy of Sulphate of Copper as 
a preventive of Potato Disease, Mr. E. E,iley of Hessle, Hull, 
brought to my notice that, during his tour, he had come across an 
instance of a farmer who was trying the remedy, but the sulphate 
of copper he was using, instead of giving a bright blue solution, 
formed a greenish coloured one. Mr. Riley therefore sent me up a 
.sample of the supposed sulphate of copper, and on examination I 
found it io contain a very considerable admixture of the much 
cheaper salt sulphate of iron (green vitriol). The two crystalline 
salts had been ground up together, so as to allow the blue colour of 
the copper salt to predominate. As there is a likelihood of the use 
of sulphate of copper extending, it is well to put farmers on their 
guard against buying it when adulterated with sulphate of iron. If 
purchase of ground-up powders be avoided the difficulty will not be 
experienced, inasmuch as the large blue crystals of sulphate of 
copper are easily distinguishable, when separate, from the green 
ones of sulphate of iron, whereis, if ground together, the admixture 
may not be apparent to the eye. 
During the year I have contributed the following papers to the 
J ournal of the Society : — 
No. "N". Indian Agriculture in its Physical Aspects. 
„ Annual Report of the Consulting Chemist for 1889 and 1890. 
Xo. "S' [. Field Experiments at Woburn in 1889 and 1890. 
„ Experiments conducted by Local Agricultural Societies in 1889 
and 1800. 
No. VII. The Trials of Cream Separators at Doncaster. 
„ The Comparative Feeding Values of Decorticated and Undecorti- 
cated Cotton-cake. 
No. VIII. Annual Report of the Consulting Chemist for 1891. 
„ The Sampling of Manures and Feeding-stuffs. 
