jl^ On the Edulcorat'ion of FiJh-0'iL 



OhJ'crvatlons on Vroccfs the Third. 



Tirft, This is mo'ii advantagemifly performed on train-oiL 

 called vicious whale-oil ; and the more putrid and foul it may 

 be, the greater will be the proportionable improvement, elpe- 

 cially if there be no mixture of the other kinds of fiOi-oil?, 

 particularly the feal, which do not admit of being edulco- 

 rated perfe«R;lv by means of heat, but require otfjcr methods : 

 but when the vicious oil is pure from admixture ot others, 

 however ftinking it may be, the bad fmell will be removed 

 bv this proccfs dulv executed, and the brown colour changed 

 to a very light amber ; and theie qualities will be much more 

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

 the degree of purity to which it is brought, be fubjeft to 

 putrefy again under a great length of time, whether it be 

 kept open or in clofe veflels. 



The oil in this ftate will bum away without leaving the 

 leaft remaius of foulnefs in the lamp; and, being rendered 

 more fluid than before, will go further, when ufcd in the 

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

 more ealily fooured from the wool. 



Ifj neveVthelcfs, there be any branches of the woollen ma- 

 nufacl:ure which require the ufe of a more thick and un£luous 

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

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

 fectly incorporate with the oil, tlni fluidity and tranfparency 

 being ftill prefervcd, as well as all the other qualities that 

 render it fuitable to the intended purpofe. Tl^is may be moft 

 beneficially done by adding a proper quantity of the refufe 

 greafe of families, commonly called kitchen Huff, which being 

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

 folve in it, and let fall al'n its impurities or foulnefs to the 

 bottom of the veflel, and render the purified admixture a 

 confiderable faving to the manufacturers. 



Scconillj, The different qualities and difpofitions of dif- 

 ferent parcels of vicious oil with rcfpeA to edulcoration render 

 various proportions neceflary of the ingredients to be ufed. 

 The quantities Itated in the above procefs are the lead which 

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

 required ; but this may always be firfl tried : and if it be 

 found, after fix or eight hours fimniering of the mixture, 

 that no gradual improvement is making in the fuicll and co- 

 lour, but that tlie oil continues tlie fame in thofe particulars, 

 and remains alio mixed with the chalk and lime, and in a, 

 thick turbid itate, a fourth or third part of the firft quantity 

 of pearl-alhes Iliould be added, and the runuiering continued 



till 



