345 
On the Edulcoration oj Fish- Oil. 
Then superadd half a pint of water in which an ounce of 
salt has been dissolved ; and having boiled them half an 
hour, pour them into a proper vessel, and let them stand 
till the separation of the oil, water, and lime be made, as 
in the preceding process. Where this operation is per- 
formed to prepare oil for the woollen manufacture, the 
salt may be omitted ; but the separation of the lime from 
the oil will be slower, and a longer boiling will be ne- 
cessary. 
If the oil be required yet more pure, treat it, after it is 
separated from the water, &c. according to the second 
process, with an ounce of chalk, a quarter of an ounce of 
pearl-ashes, and half an ounce of salt. 
Observations on Process the First . 
This process may be performed on any kind of fish or 
seal-oil that is putrid and stinking, and will improve it in 
smell, and generally render the colour lighter, if pre- 
viously dark and brown : it will also conduce to ren- 
der these oils fitter for burning, which are, in their crude 
state, faulty in that point ; but it will not meliorate them 
to the full degree they admit of even without heat, and 
should therefore be practised when only a moderate im- 
i provement is required. 
Secondly , When the oil is taken off from the dregs 
and brine, the dregs which swim on the brine should be 
taken off it also, and put into another vessel of a deep 
form; and on standing, particularly if fresh water he 
added and stirred with them, nearly the whole remaining 
part of the oil will separate from the foulness ; or, to save 
this trouble, the dregs, when taken off, may be put to 
any future quantity of oil that is to be edulcorated by this 
method, which will answer the same purpose. 
Vol. ii, u. u 
