1892. ] NEW YORK ACADEMY OF SCIENCES. 109 
Paris, published a more complete treatise in the year 1675. These 
were the first glimmers of the dawn soon to break in chemical 
history, and especially in the domain of organic chemistry. Up to 
this time the work had been fragmentary and erratic. No ‘particular 
line of research had been followed by any experimenters and no 
leading or intelligent course laid down for future work. 
The reason for this dormant state of the organic side of chemistry 
is probably found in the development of eal: The alche- 
mists, who lived but for one object, the conversion of the base metals 
into gold, caused the drift of all experimental work in that direc- 
tion; in other words, they encouraged the inorganic rather than 
the organie development of experimental chemistry. Nevertheless, 
certain truly organic substances were discovered and their proper- 
ties pretty well known. But the healing art was almost exclusively 
confined to metallic compounds during the early part of the eighteenth 
century, and it took some time before organie medicines were used 
at all. Gradually organic bodies, especially plants, were used and 
their active principles separated from them: This led to the dis- 
covery of such bodies as succinic acid from amber, benzoic acid from 
gum benzoin, pyroligneous acid, the crude acetic acid, from wood, 
and sugar of milk from cow’s milk. 
Nicholas Lémery classified all substances under three heads, mine- 
ral, vegetable, and animal, according to their origin; and this was 
the best he could do. 
Such was about the condition of affairs in chemistry until near 
the close of the last century (1774), when the Swedish apothecary, 
Karl Scheele, made the first important advances in the investiga- 
tion of organic substances. Before this time all the organic ehemi- 
eal investigations had been made solely for the purpose of obtaining 
medicines and for the improvement of various technical processes, 
such as dyeing and calico-printing. Scheele had the true spirit of 
the scientific investizator, and made his experiments solely for the 
purpose of obtaining a better knowledge of the character of the 
materials that fell into his hands. He was the first to identify and 
separate nearly all the common vegetable acids. He proved that 
the acid of lemons (citrie acid) was different from the acid of grapes 
(tartaric acid), and that malie acid (from apples) is different from 
either. He also separated and described the acid of wood-sorrel 
(oxalic acid), and proved.that it could be made from sugar by means 
of nitric acid. Furthermore, he showed that another acid (lactic) 
of a totally different character was obtained from sugar of milk by 
the same treatment with nitric acid. From nut-galls he obtained 
gallie acid; and from urine, uric acid; and by treating fats with 
oxide of lead and water he obtained the sweet principle of oils—as 
he called it—glyecerin, at the same time proving that by treatment 
with nitric acid glycerin will give the same product as ordinary 
eane-sugar, namely, oxalic acid. 
Chemistry owes to pharmacy a debt of gratitude for showing the 
way to ber modern fields of triumph, for the earliest and best 
