338 
On the Edulcoration of Fish- Oil. 
The use of lixiviate salts alone is not, however, the 
most expedient method that can be pursued for the edwb 
coration of oils, for several reasons. If they be used 
alone, cold, in the requisite proportions, they coagulate a 
considerable part of the oil, which will not again sepa- 
rate from them under a very great length of time; and 
when they have destroyed the putrid scent, a strong bit- 
ter empyreumatic smell remains. The same inconve- 
nience, with relation to the coagulation of part of the oil, 
results when they are used alone with heat. The super- 
addition of common salt (which resolves the coagulum 
and counteracts the saponaceous power of the lixiviate 
salt, by which the oil and water are made to combine) is 
therefore necessary ; and the expense arising from the 
larger proportion of lixiviate salt requires it to be em- 
ployed if no other alkali be taken in aid, and renders the 
junction of alkaline earths with it extremely proper in the 
edulcoration of oils for commercial uses. Lime has also 
an edulcorative power on animal oils ; but it has also so 
strong a coagulative action, that the addition of a large 
proportion of alkaline salts becomes, when it is used, ne- 
cessary to reduce the concreted oil to a iluid state ; and 
therefore this substance alone is not proper for that pur- 
pose. The combination of lixiviate salt with lime, or 
the solution commonly called soap -lye, has an effectual 
edulcorative action on foetid oils ; but it makes a trouble- 
some coagulation of part of the oil if no common salt be 
employed, and must be used in such large proportion, if 
no alkaline earth be added, as renders the method too ex- 
pensive. 
Lime has a power of combining with and absorbing 
the putrid parts of the gelatinous fluid and bile when 
commixed with oil, and effects, either with or without 
heat, a considerable edulcoration of foetid oils ; but it com 
bines so strongly with them, either cold or hot, that the 
