76 PHILOSOPHY OF ZOOLOGY. 



As these impurities are chiefly contracted in the prepar- 

 ation of the oil, from the blubber and livers, it would be of 

 consequence to examine, how far the various processes 

 which have been recommended, might be employed with 

 advantage, by the original manufacturer ; or rather to de- 

 vise means by which the oil might be extracted, without, 

 At the same time, obtaining along with it, those substances 

 which render it too thick for burning in lamps, and dis- 

 agreeable on account of its smell. 



Many other substances secreted by different animals, 

 deserve to be enumerated in this place, such as Castor, 

 Civet, and Musk, but their characters are too imperfectly 

 ascertained, to enable us to go into detail. The facts known 

 concerning them, will be given when treating of the organs 

 in which they .ire formed. 



9. Adds. The acids which we have now to enumerate, 

 consist of various proportions of carbon, hydrogen, oxygen 



except a hot, greasy, soap-like scent. 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 separa- 

 tion of the oil, water, and lime be made, as in the preceding process."?. 

 ** 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 quar- 

 ter of an ounce of pearl ashes, and half an ounce of salt.'* 



The fourth process, u Which may be practised alone, instead of process 

 the lirst, as it will edulcorate and purify fish-oil to a considerable degree, so 

 as to answer most purposes, and for process the third, when the whole is 

 performed. 



" Take a gallon of crude stinking oil, and put it to a pint of water pour- 

 ed off from two ounces of lime slacked in the air ; let them stand together, 

 and stir them up several times for the first twenty -four hours ; then let 

 them stand a day, and the lime water will sink below the oil, which must 

 be carefully separated from them. Take this oil, if not sufficiently purified 

 for your purpose, and treat it as directed in process the third, diminishing 

 the quantity of pearl-ashes to one ounce, and omitting the lime and chalk." 

 liU-wisr, some judicious observations in " SCOKESBV'* Account of 

 the Arctic Region*," vol. ji. p. 408, 43?, 



