48 
Arrticze III. 
On the Composition of Stearic Acid, and the Products of its di- 
stillation. By Proressor REDTENBACHER Of Prague*. 
[From the dnnalen der Chemie und Pharmacie, vol. xxxv. p.190, for July 1840. ] 
WE owe our knowledge of stearic acid, as well as of other fatty 
bodies, to the classical labours of Chevreul, as made known to us 
in his Recherches sur les corps gras. Since that time no one 
has further investigated this acid, no new analysis of it has been 
published, and all subsequent investigations have been founded 
upon these first results. Nevertheless, chemical science gene- 
rally, as well as the methods by which the constituents of organic 
bodies are ascertained, have since made very important advances, 
especially in those points which at that time were the most dif- 
ficult. 
If we read the methods by which Chevreul determined the 
composition of the fat bodies, and consider only the great num- 
ber of estimations of volume, with the necessary corrections of 
each analysis, which were requisite, besides those numerous pre- 
cautions which indeed are still indispensable, we can only wonder 
at the great perseverance and accuracy with which that great 
naturalist conducted so many analyses, independently of the high 
scientific results which his work afforded. But notwithstanding 
the great talents of the observer, exactly with these imperfect 
methods rested the greater probability of an error, which, though 
in itself small, could easily in the fats, with their high atomic 
weights, amount to from one to two atoms of aconstituent. The 
researches themselves, as was at that time customary, do not 
furnish us with the actually observed numerical results, but only 
those numbers which were deduced from them, so that a close 
examination of them, as well as all reasoning respecting them, is 
impossible. Besides, the science at that time was not ac- 
quainted with the great accuracy as well as the general appli- 
cability of estimating the atomic weights of organic acids by 
means of their silver-salts. 
* Translated by J. H. Gilbert, Ph. D. 
