|0 PURIFICATION OF FISH-OIL. 



or more difficult to be obtained, they may be rejected from; 



the number of ingredjenis that are proper for the purifying of 



oils, with a view to commercial advantages, 



Sea-falt ufeful Sea-falt has an antifeptic power on the mixed folid parts of 



in mixtures but an ; ma ] s . but ufed alone, or diifolved in water, it does not 

 not alone. ' 



appear to letter) the putrid fetor of oils, but on the contrary 



rather increafes it. If, after their commixture with it, they 

 are fubjecled to heat, it rather depraves than improves the 

 oils ; but though by its own immediate aclion on them it 

 conduces fo little to the edulcoration of oils, yet it is a me- 

 dium for the feparation of water and the alkaline fubftances 

 requifite to be employed to that end. It is of great utility in 

 the ecjulcorative procefles : for when alkaline falts or earths 

 combine with the water neceflary to their action on the oils, 

 or themfelves form coagulums or corrections with it, a folu- 

 tion of fait will loofen the bond and diflblve the clofe union ; 

 fo that the oil being feparated will float on the aqueous fluid, 

 while the earth, if any be in the mixture, will be precipi- 

 tated and fink clofe together to the bottom of the containing 

 veflel. 

 Muriate of Sal catharticus, glauber fait, nitrum vitriolatum, tartar, and 



ttjj ™jj ate Other neutral falts, though they counteraa putrefaftion in the 

 potafh, &c. of mixed or folid parts of animals, feem to have little, effect on 

 little value- j| s w ;t n refpecl to their edulcoration, and cannot therefore 

 be ranked amongft the fubftances proper to be ufed for that 

 purpofe. 

 Oxide of lead is Lead reduced to the ftate of a calx, either in the form of 

 very powerful, m j mum or litharge, has a ftrong edulcorative power on fetid 

 oils, and is indeed applied to that end, wi^h refpect to one 

 kind of vegetable oil, for a very bad purpofe, confidering its 

 malignant qualities on the human body. 



In the cafe of train-oiJ, which will fcarcely ever be con- 

 fidered among the efculent kinds in this country, the fame 

 objection againft its ufe would not lie ; and employed either 

 with or without heat, it is a powerful abforbent both of the 

 putrid and empyreumatic parts that occafion the foetor. 

 but was reje&ed As however there may be fome prejudice againil its ufe, 

 from prejudice. even \ n an y way, and as it is not abfolutely neceflary, I have 

 not given it a place among the ingredients of the procefles I 

 recommend. 



The 



