SUS SCROFA. 



is irritating to the skin, and sometimes exercises an injurious 

 reaction on substances mixed with it. 



In the United States, where swine are raised so abundant- 

 ly, oil is now very extensively separated from lard. Its close 

 connection with the question of disposing of the agricultural 

 products of the Union, and especially of the Western States, 

 forms a reason for giving it an extended consideration. 



LARD-OIL is considered much superior to olive or sperm 

 oil, for machinery, and for the manufacture of woollens, &c. 

 It can be furnished also at half the price, and therefore it will 

 doubtless supersede that article of import. As it contains 

 less stearine than other oils, it is found much better for comb- 

 ing wool, for which purpose a single factory wished to con- 

 tract for ten thousand gallons from one establishment. 



Repeated experiments have shown, that for the purpose of 

 combustion no oil is superior. It is important, in trying it 

 with this view, to obtain a good article, manufactured from 

 good lard, and not from the dark-burned which creates smoke 

 and clogs the flame. For want of sufficient care in this re- 

 spect, some have no doubt met with disappointment in their 

 attempts to substitute this oil for sperm oil in their lamps. 



The following are given as the relative constituents of lard 

 oil and sperm oil, in one hundred parts of either: 



Carbon. Oxygen. Hydrogen. 



Lard oil, . . 79.03 9.548 11.422 



Sperm oil, . . 79.5 8.9 11.6 



It will thus be seen that the difference in carbon is only .47, 

 in hydrogen about .18, while in oxygen it is over .60 in favor 

 of the lard-oil. The large quantity of carbon proves that 

 it may be relied on as a material for giving light, as it is 

 well known that, whenever carbon predominates in an animal 

 oil, the article is capable of a high degree of luminous power. 

 Experiments have been made which have shown results in 

 favor of lard-oil. About 60 Ibs. in 100 of good lard, in tallow 

 only 28, are oil, and the process of manufacture resorted to 

 shows that it may be made a profitable business. Large or- 

 ders have already been executed at the West for this oil, to 

 be used in the Eastern States. 



The heat of lard oil for the blow-pipe has been found to be 

 much greater than that of sperm. Lard itself melts at 97 

 Fahrenheit; its specific gravity at 60 is 0.938. Lard crystal- 

 lizes in small globules, sperm in flakes or scales. It is soluble 



7 



