172 | TIMEHRI. 
soluble in alcohol of a strength of 40 o/o over proof, but insoluble or 
with difficulty soluble in alcohol of 25 o/o under proof, whilst in other 
cases the cloudiness has been traced to empyreumatic products, derived 
from gas liquor, present in the sulphate of ammonia which had been 
added to the wash to accelerate the fermentation. 
Both these causes are easily overcome; in the first case by care in 
burning the colour, in the second by avoiding the use of sulphate of 
ammonia prepared from gas liquor, and which may contain empyreuma- 
tic products. It is advisable that the sulphate of ammonia used for the 
purpose of accelerating fermentation should always be “ bone” sulphate 
of ammonia prepared from bones and not the usual quality obtained 
from gas liquor or from the by-products of coke ovens, 
Under these circumstances the Agricultural Committee of the Royal 
Agricultural and Commercial Society requested me to enquire into this 
matter, and this, assisted by the experience and advice cf Mr. Scard, I 
have done. 
At the commencement of the enquiry it was found that the water 
supply of Liverpool, from which port the complaints have almost all 
been derived, is obtained from two sources, one being upland surface 
water, the other water pumped from deep wells sunk in the new red 
sandstone. Water derived from deep wells in the new red sandstone 
not unfrequently contains in solution calcium sulphate and salts of mag- 
nesium, and it appeared to me that the cloudiness complained about 
might be due to the presence of these salts in the water used for testing 
and not to defects in the rum. 
To examine into the possibility of this, weak solutions of sulphate of 
of calcium in water were prepared and used for the purpose of diluting 
pure alcohel of 45 0/0 over proof. It was found that when the alcohol 
was diluted to the strength of 25 o/o under proof with water containing 
more than 5.6 grains per gallon of calcium sulphate, precipitates of 
this salt occurred at temperatures of from 80 to 86° F. but that when 
water containing less than 5.6 grains and more than 2,5 grains per 
gallon was used it remained clear at 84° F, but became distinctly cloudy 
and opalescent when cooled to 50° F. When water containing less 
than 2.5 grains per gallon was used the diluted spirits remained clear 
even at the lower temperature. 
It was evidently necessary to repeat these experiments with Liverpool 
water, both that obtained from the well and that from the upland 
sources, Messrs Booker Bros. & Co, very kindly obtained for mea 
