678 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1907. 
The ideas of the professor were from the first warmly opposed, but — 
soon Hellriegel and Wilfarth, Schlesing and Laurent, Winogradski, 
brought in from every side important contributions to the question of 
the absorption of nitrogen and demonstrated in a startling manner 
the truth of the ideas put forth by Berthelot. 
This, moreover, was not the only occasion upon which Berthelot, 
was actively disputed by opposing scholars. A posthumous memoir 
of Claude Bernard towards 1878 was the text of a most scholarly and 
most earnest scientific discussion between Berthelot and Pasteur. 
The latter held, on the basis of experiments, that the fermentation of 
glucose absolutely demanded the presence of leaven or barm of beer, 
while, according to Berthelot, the transformation of glucose into alco- 
hol could take place through the intermediary of a ferment that was 
not living, of a diastase emitted by the yeast itself. The two scholars 
maintained their positions without reaching a common conclusion. 
Twenty years afterwards a German scholar, Buchner, demonstrated 
that yeast, sufficiently compressed, furnished a liquid without trace 
of living cells and capable of continuing for some time the fermenta- 
tion of sugared juices. Berthelot’s instinct of genius had surmounted 
Pasteur’s experimental skill. 
Having acquired a knowledge of the ancient languages, Berthelot 
was exceptionally well fitted to study the history of chemistry in 
early times. In the “ Origines de l’Alchimie ” he shows that alchemy 
was founded on a doctrine of philosophy, that of the sameness of 
matter molded as if formed of four elements. Its practice rested 
upon the actual experiments performed by the Greco-Egyptian gold 
and silver smiths and metallurgists. This the author indisputably 
established by the comparative study of a papyrus found in Thebes 
and some receipts of the pseudo-Democritus, in a second work en- 
titled “ Introduction a l’étude de la chimie des anciens et du moyen- 
age. oy) 
Berthelot was led in this connection to publish the Greek, Syriac, 
and Arabic alchemic texts, which up to this time had remained un- 
published, with the collaboration of distinguished lnguists—Messrs. 
Rouelle for the Greek, Rubens Duval for the Syriac, and Houdas for 
the Arabic. Thus was again built up an entire branch of the science 
of the early times, theretofore almost unknown. Furthermore he 
pursued his studies up to the fourteenth century, in order to ascertain 
by what means the science of alchemy had penetrated into the Occi- 
dent. He found that these means were two: First, by the handing 
down of the arts and industries which had up to eh time been Aig: 
completely ignored and which nevertheless had subsisted continuously 
since the fall of the Roman Empire, and second, by the Syriac trans- 
lations of the Greek alchemists, equally ‘easaail which were the 
