Louis Pasteur

8 LOUIS PASTEUR
to transform everyday life. For instance, when Daguerre and
Niepce invented photography in 1835, "daguerreotypes" became
overnight a popular fad, and frequently reached such a high level
of technical perfection as to give them great documentary and
artistic interest. it Photography, then appeared, was to do for the
recording of the external forms of nature what printing had done
for the recording
of
thought.
Chemistry was abandoning the romantic den in which the
alchemist had pursued the elixir of life and the dream of
gold.
Lavoisier, who initiated the modern era of theoretical chemistry,
started his scientific life by collaborating in the preparation of an
atlas of the mineralogical resources of France. Elected a member
of the Royal Academy at the age of twenty-five, he prepared
reports on a variety of technical problems.
This made him familiar
with the operations of most of the national industries: mines, iron
and bleaching works, starch and soap factories, and others. He
also improved the manufacture of saltpeter and gunpowder. It
was in part his work on the Paris water supply and his interest
in mineral waters that led him to investigate the chemistry of
water, and his classical studies on the composition of air originated
from his efforts to design lanterns for the lighting of Paris.
During the eighteenth and early nineteenth centuries France
was leading Europe in theoretical and industrial chemistry, and
her self-sufficiency during the Revolutionary and the Napoleonic
Wars was in no small part the result of her scientific superiority.
The place of chemistry in the economy of the rest of the world
continued to expand after the Napoleonic Wars. Disasters like
the mine explosion
of 1812 near Gateshead-on-Tyne led Humphry
Davy to study the behavior of firedamp, and to demonstrate that
explosion would not pass through fine gauze. In 1816 he devised
the safety lamp, which decreased the hazards in coal mining and
thus contributed to the industrial supremacy of England. The
synthesis of urea by Wdhler in 1828 opened the way for the
synthesis of medicaments and dyestuffs. Even the technology of
food was influenced by the new knowledge. Marggraf applied