science. Albertus Magnus, who taught at Paris,
wrote no less than sixteen treatises on chemical subjects, and,
notwithstanding the fact that he was a theologian as well as a
scientist, and that his printed works fill some _fifteen folio volumes_,
he somehow found the time to make many observations for himself, and
performed numberless experiments in order to clear up doubts. The larger
histories of chemistry accord him his proper place, and hail him as a
great founder in chemistry, and a pioneer in original investigation.

Even St. Thomas of Aquin, much as he was occupied with theology and
philosophy, found some time to devote to chemical questions. After all,
this is only what might have been expected of the favorite pupil of
Albertus Magnus. Three treatises on chemical subjects from Aquinas' pen
have been preserved for us, and it is to him that we are said to owe the
use, in the Western world at least, of the word amalgam, which he first
employed in describing various chemical methods of metallic combination
with mercury that were discovered in the search for the genuine
transmutation of metals.

Albertus Magnus' other great scientific pupil, Roger Bacon, the English
Franciscan friar, followed more closely in the scientific ways of his
great master, devoting himself almost entirely to the physical
sciences. Altogether he wrote some eighteen treatises on chemical
subjects. For a long time it was considered that he was the inventor of
gunpowder, though this is now known to have been introduced into Europe
by the Arabs. Roger Bacon studied gunpowder and various other explosive
combinations in considerable detail, and it is for this reason that he
obtained the undeserved reputation of being an original discoverer in
this line. How well he realized how much might be accomplished by means
of the energy stored up in explosives, can, perhaps, be best appreciated
from the fact that he suggested that boats would go along the rivers and
across seas without either sails or oars, and that carriages would go
along the streets without horse or man power. He considered that man
would eventually invent a method of harnessing these explosive mixtures,
and of utilizing their energies for his purposes without danger. It is
curiously interesting to find, as we begin the twentieth century, and
gasolene is so commonly used for the driving of automobiles and motor
boats, and is being introduced even into heavier transportation as the
most