4 
34 Dr. Playfair’s Lecture on the Great Erhibition of 1851. 
Another great improvement now took place. In preparing the — 
commercial stearine from palm-oil or tallow, it is essential to re- — 
move the glycerin, and this had been accomplished by saponify- 
ing them with alkalies. Sulphuric acid, acting on fats, unites 
with the oily acids and with glycerin; the former compounds 
are decomposed by water and become insoluble, while the latter, 
from being soluble, is removed; the oily acids, blackened with — 
the destroyed organic impurities, are now distilled, and it is found — 
that a jet of steam, heated somewhat in the manner of the hot — 
blast, aids their distillation, the fatty acids passing over in acom- | 
paratively pure form, while the residual black resinous matter is — 
made into black sealing wax. Candles may now be made from — 
the distilled fatty acids at once, or they may be pressed to remove t 
the oleic acids. 
The oleic acid, both from this mode of manufacture and from 
that by alkaline saponification, is principally exported to France, 
P 
most impure and foetid fats; by its means, the finest candles — 
may be madé from the waste of the glue-maker and from the — 
oily residues obtained by the decomposition of the waste lyes of 
the woollen manufacturer and the bleacher. — As the first beauti- = 
ful process of saponification sprang from the abstract researches _ 
of Chevreul, so has the last elegant method arisen from the sci* of 
entific investigations of Frémy, although both of them have 
been reduced to practice, with many improvements, by the man- — 
he importance of the manufacture may — 
be understood when I state that one chbmpany (Price’s Candle 
ufacturers themselves. " 
Company) possesses cocoa-nut plantations in Ceylon, and em- 
ploys eight hundred workmen in its five manufactories in Lon-_ 
don, using a capital of nearly half a million, and dividing profits — 
to the extent of 40,0007. per annum. 
emistry has not yet done so much for the manufacture ‘ 4 
is sti 
wax candles as might have been anticipated. 
bleached by exposure to air and light, and the Operation has been 
hastened more by mechanical than by chemical contrivances; - 4 
the bleaching of wax is a tedious and often a difficult process, — 
and demands greater attention from chemists than it has received; 
the Brazilian mahogany-colored wax, produced by a black bee | 
hiving under ground, has not yet been bleached by the sun, and — 
might be imported in considerable quantity if Chemistry offer 
means for removing its color. I do not allude to what Chemistry 
— to do, but it would appear that paraffin and oil from coal, 
nd possibl . 
the necessity for sperm 
. ee 
y from peat, may dispense, to a certain extent, with 
