792 Quarterly Report of the Chemical Committee, Dec., 1893 . 
given along with it. Three tons had been purchased at Gl. 10s. per 
ton. Dr. Voelcker’s analysis showed that, though the results were 
equal to the figures guaranteed, yet the manure was not bone 
manure at all, but a mixture of shoddy and mineral superphosphate, 
and that hence the description given was an incorrect one. The 
manufacturers ultimately agreed to take it. per ton nett for the 
manure, instead of the Gl. 10s. per ton originally charged. 
Slay . — A word of warning was given in the Journal of June 30, 
1893 (Vol. IY. Part II. page 361), cautioning farmers against pur- 
chasing, under the name of slay, an article worthless for manurial 
purposes, in the belief that they were being supplied at a low price 
with basic slag, a material possessing intrinsic value. That the sale 
of this article continues is shown by another case in which a Member 
who intended to purchase 60 tons for his grass land, at 30s. a ton, 
sent a sample to Dr. Voelcker for analysis. Dr. Voelcker reported 
that “it was not basic slag at all, but an almost worthless material 
containing but a trace of phosphoric acid, whereas basic slag should 
have about 17 per cent.” As a consequence of this report no 
purchase was made by the Member. 
Horn Dust . — A sample of what was called “ Pure Horn Dust,” 
and the price of which was 21. 10s. per ton, was reported upon by 
Dr. Voelcker as containing very little horn dust at all, the greater 
part being vegetable ivory with some small amount of bone, and the 
price asked being much beyond its value. It was subsequently 
ascertained that a sample had been received from a man who pro- 
fessed to buy horn dust at the Sheffield workshops and to retail it 
amongst farmers. In consequence of the analysis no purchase was 
made. 
Linseed Cake adulterated with Rice Oil . — The following case is 
important as bringing to light a new form of adulteration practised, 
and one which may, unless care be exercised by the analyst, 
readily escape detection. It exemplifies also the risk of accepting 
the term oil cake in place of that of linseed cake, and of the buyer 
being content with any guarantee of oil which does not stipulate 
that the oil shall be linseed oil or, what is synonymous with this, 
that the cake shall be pure linseed cake. 
It is believed that linseed meal, from which the oil had been in 
great measure removed, had in this instance been mixed up with rice 
oil, so that the figures of analysis, though apparently reading well 
and showing a cake rich in oil, represented hardly any linseed oil 
at all, but only the greatly inferior rice oil. 
A Member sent a sample of cake, 4 tons of which he had pur- 
chased at 'll. 15.9. per ton. The circular sent by the vendors con- 
tained under the general heading of Linseed Cakes the following 
item : — 
“ Bombay (very fine), guaranteed 13 to 16 per cent, oil.” 
When, however, the invoice was received, the cake was merely 
