J4 PURIFICATION OF FISH-OIL* 



in which an ounce of fait has been diflblved ; and having 

 boiled them half an hour, pour them into a proper vefTel, and 

 let them (land till the feparation of the oil, water, and lime 

 be made, as in the preceding procefs* Where this operation 

 is performed to prepare oil for the woollen manufacture, the 

 fait may be omitted ; but the feparation o( the lime from the 

 dil will be flower, and a longer boiling will be neceffary* 



If the oil be required yet more pure, treat it, after it is fe- 

 parated from the water, &c. according to the fecond procefs, 

 with an ounce of chalk, a quarter of an ounce of pearl-afhes, 

 and half an ounce of fait* 



Obfervations on Procefs the Firji. 



Ob&t7*ti<ms» This procefs may be performed on any kind of fifli or fea- 



oil that is putrid and (linking, and will improve it in fmell, 

 and generally render the colour lighter, if previoufly dark and 

 brown : it will alfo conduce to render thefe ails fitter for burn- 

 ing, which are, in their crude ftate, faulty in that point ; but 

 it will not meliorate them to the full degree they admit of even 

 Without heat, and ftlould therefore be praclifed when only a 

 moderate improvement is required. 



The dregs may Secondly, When the oil is taken off from the dregs and 



be a?ed. brine, the dregs which fwim on the brine (hould be taken off 



it alfo, and put into another vefTel of a deep form ; and oil 

 landing, particularly if frefh water be added and ftirred with 

 them, nearly the whole remaining part of the oil will feparate 

 from the foulnefs ; or, to fave 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 anfwer the fame 



, purpofe. 



Objervdtiom on Procefs the Third. 



Procefs 3 is beft Firft. — This is moft advantageoufly perfof med on traifi-oiJ, 

 Jer train-oil. ca ]| ec i vicious whale-oil ; and the more putrid and foul it may- 

 be, the greater will be the proportional improvement, efpe. 

 dally if there be no mixture of the other kinds of rifh-oils, 

 particularly the feal, which do not admit of being edulcorated 

 perfectly by means of heat, but require other methods : but 

 when the vicious oil is pure from admixture of others, how- 

 ever (linking it may be> the bad fmell will be removed by this 

 procefs duly executed, and the brown colour changed to a 



Very 



