Annual Report for 1892 of the Consulting Chemist. 791 
diminution in its sale. But there is a difference in the case of cakes 
sold for manurial purposes. An admixture of sand or other im- 
purities will certainly affect the value, but it will not, as might be 
the case with a feeding material, endanger the health of stock. The 
only satisfactory remedy appears to me to be for the purchasers to 
insist upon buying manure Rape-cakes according to analysis, and 
only to pay a price in accordance with the quality of the cakes. This 
would, I think, be a much better plan than to fix any percentage up 
to which amount admixture will be allowed. 
* » 
White- LEAD. 
Adulteration of White-lead. — White-lead is an article which is 
used extensively upon farms and estates, but which is frequently 
found to be adulterated. 
A sample sent to me by a member gave the following analysis : — 
Oil . . . . . . 11-23 
Sulphate of lead . . . . . 53-84 
Sulphates of baryta and lime . . . * . . 28-83 
Oxide of zinc . . . . ’ . ’ . * . . 6-10 
100-00 
This was not a genuine White-lead, but contained a considerable 
admixture of sulphate of baryta and lime, with some zinc compounds, 
none of which materials should occur in pure White-lead. 
Waters. 
As usual, a considerable number of samples of water have been 
included among the analyses done for members of this Society. 
Acid Water from a Colliery . — In one instance, when a sample of 
water was sent to me, it was stated thp,t a heifer which had been 
drinking of the water of a brook had died. The post-mortem indi- 
cated the presence of an irritant poison, and traces of free sulphuric 
acid, as well as an abnormal quantity of iron, were detected in the 
contents of the stomach. The analysis of the water confirmed these 
observations, and showed there not only was a great quantity of iron 
present in the water, but also that the water had a distinctly acid 
reaction, and contained 2‘63 grains per gallon of free sulphuric acid. 
On subsequent inquiry it was found that the washings from a 
colliery or coal-pit ran into the brook two or three hundred yards 
above the spot where the heifer had been drinking. 
3 H 
VOL. m. T. s. — 12 
