PURIFICATION OF FISH-OIL. }J 



very light amber ; and thefe qualities will be much more per- 

 manent in this than in any crude oil, as it will not, from the 

 degree of purity to which it is brought, be fubject to putrefy 

 again under a great length of time, whether it be kept open 

 or in clofe ve(fels. 



The oil in this (late will burn away without leaving the leaf! It will then bur* 

 remains of foulnefs in the lamp : and, being rendered more clcar » * c% 

 fluid than before, will go further, when ufed in the woollen 

 manufacture, than any other kind, and will be much more 

 eafily fcoured from the wool. 



If neverthelefs there be any branches of the woollen manu- Kitchen-fluff 

 facture which require the ufe of a more thick and unctuous JJ^n , J^ ., 

 oil, this may be rendered fo by the addition of a proper quan- is wanted. 

 tity of tallow or fat, of which a certain proportion will per- 

 fectly incorporate with the oil, the fluidity and transparency 

 being ftill preferred, as well as all the other qualities that " 

 render it fuitable to the intended purpofe. This may be rnoffc 

 beneficially done by adding a proper quantity of the refufe 

 greafe of families, commonly called kltchen-jluff, which being 

 put to the oil, when moderately heated, will immediately dif- 

 folve in it, and let fall alfo its impurities or foulnefs to the 

 bottom of the veflel, and render the purified admixture a con- 

 siderable faving to the manufacturers. 



Secondly. The different qualities and difpofitions of dif- Tn # e quantities 

 ferent parcels of vicious oil with refpect toed ulceration, render mJ^S^riSS 

 various proportions neceflary of the ingredients to be ufed. 

 The quantities Hated in the above procefs are the leaft which 

 will effect the end in general, and frequently greater will be 

 required; but this may always be firft tried ; and if it be found, 

 aflcr fix or eight hours fimmering of the mixture, that no gra- 

 dual improvement is making in the fmell and colour, but that 

 the oil continues the fame in thofe particulars, and remains 

 alfo mixed with the chalk and lime, and in a thick turbid (rate, 

 a fourth or third part of the firft quantity of pearl-afhes mould 

 be added, and the fimmering continued till the oil be perfect. 

 As the quantity of the water is leflened by the evaporation, it 

 is neceffary to make frefh additions from time to time, that 

 there may be always nearly the original proportion. 



Thirdly. If it be inconvenient to give the whole time of and the boiling 

 boiling at once, the fire may be fuffered to go out and be re* P s !.f orme(1 .* t 

 Kindled at any diltance ot time ; an i jr, m fuch cafe, a imall 



proportion 



