188 Annual Report of the Consulting Chemist. 
glass or earthenware vessels. We have found that whilst some 
of the finest and best prepared butters undergo little or no 
change, there is in others a gradual disappearance of the cha- 
racteristic principles of butter, and a consequent assimilation to 
the constitution of an ordinary animal fat. This change, which 
appears to be due to an incipient fermentation, and is generally 
accompanied by the development of fungi, is probably caused 
either by the use of sour cream or by insufficient care in making 
the butter.* 
Laboratory, Somerset House, 
31st May, 187G. 
VII. — Annual Report of the Consulting Chemist for 1876. 
By Dr. Augustus Voelckek, F.R.S. 
In presenting the customary Annual Report on the chemical 
work done by the Consulting Chemist, I would remark that the 
number of analyses made for Members of the Royal Agricul- 
tural Society during the period between December, 1875, and 
December, 1876, has exceeded that of last year by 16, and has 
reached 720, which number has been exceeded only once, and 
then only by 10, viz. in 1871. 
The increase, as will be seen by the appended tabulated 
summary, is due mainly to the unusually large number of 
oilcakes which were sent to the laboratory for examination. 
Some cases of grossly adulterated linseed-cakes have come 
under my notice ; but as these have already been referred to 
in my Quarterly Reports, no further mention of them is re- 
quired in the Annual Report, and I only allude to them for the 
purpose of observing that few cases of that kind have come 
under my notice in 1876. It must not, however, be inferred 
from this remark that cakes which are now sold in England as 
" pure " or " genuine " linseed-cakes are, with few exceptions, 
* The commercial value of butter is affected by flavour more than by any 
other consideration, and this unfortunately cannot be expressed by an analysis, 
however carefully it may have been made. There is, however, one point which 
will be noticed at once on glancing at the butter-analyses in Table II., and which 
appears to have escaped Mr. Bell's notice. It will be perceived that the per- 
centage of curd in different samples of butter varies greatly. Of all constituents 
of butter, the curd tends most to spoil it in keeping. The more effectually the 
curd is removed, or what comes to the same thing — the more effectually butter is 
washed and kneaded, the better it keeps, and the finer will be the flavour, other 
circumstances being the same, when the butter is brought to market. Butter 
full of butter-milk always contains comparatively much curd, and in warm 
weather such butter becomes rancid iu a very short tune, say in a few dnvs. 
—[Edit.] 
