98 TIMEHRI. 
trace of them, in the following ages. In this case, as in 4 
many other circumstances, the men of the 16th century 
saw what constitutes the most advanced progress, but by 
a kind of intuition and without possessing those clear — 
notions and exaét principles of physics, without which 
progress remains but accidental and fleeting. 
Another more lasting improvement was that of the 
worm. The alembics of the Greeks permitted them no 
doubt to obtain distilled liquids, but on the condition 
that they worked very slowly and with a very low heat. 
In faét, the vapours condensed but badly in the tubes 
and caps with small surfaces represented in the manu- 
scripts. However little they tried to push on the dis- 
tillation, the receivers become heated and condensa- 
tion was almost impossible. Thus the old writers 
dire€ted that their apparatus should be heated over 
very small fires. They worked with intermediary baths 
of sand or ashes, or of water. The name of Bain 
Marie applied to the kitchen apparatus of the present 
day affords a remote souvenir of MARIE the Egyp- 
tian alchemist. They often confined themselves to 
carrying on distillation by the mere heat of fermenting 
manure or at most by a slow fire of dung or saw dust, 
Hence their operations were so slow, that their distil- 
lations took days and weeks. ‘It requires 14 days or 21 
days says one book, to accomplish the operation.” Thus 
not only were the effects of operations intended to cause 
sulphurous and arsenical substances to penetrate little by 
little into the heart of metallic laminz when subje€ted to 
the aétion of elixirs, secured, but the evaporation and 
colleétion of liquids placed in the alembics were also — 
rendered praéticable. 
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7 
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