rposes without {54} 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 on railroad cars in the West
as the most available source of energy for suburban traffic, that this
generation should only be fulfilling the idea of the old Franciscan
friar of the thirteenth century, who prophesied that in explosives
there was the secret of eventually manageable energy for
transportation purposes.

Succeeding centuries were not as fruitful in great scientists as the
thirteenth, and yet at the beginning of the fourteenth there was a
pope, three of whose scientific treatises--one on the transmutation of
metals, which he considers an impossibility, at least as far as the
manufacture of gold and silver was concerned; a treatise on diseases
of the eyes, of which Professor Allbutt [Footnote 4] says that it was
not without its distinctive practical value, though compiled so early
in the history of eye surgery; and, finally, his treatise on the
preservation of the health, written when he was himself over eighty
years of age--are all considered by good authorities as worthy of the
best scientific spirit of the time. This pope was John XXII, of whom
it has been said over and over again by Protestant historians that he
issued a bull forbidding chemistry, though he was himself one of the
enthusiastic students of chemistry {55} in his younger years and
always retained his interest in the science. [Footnote 5]

[Footnote 4: Address cited]

[Footnote 5: For the refutation of this calumny with regard to John
XXII, see "Pope John XXII and the supposed Bull forbidding
Chemistry," by James J. Walsh, Ph. D., LL. D., in the _Medical
Library and Historical Journal_, October, 1905.]

During the fourteenth century Arnold of Villanova, the inventor of
nitric acid, and the two Hollanduses kept up the tradition of original
investigation in chemistry. Altogether there are some dozen treatises
from these three men on chemical subjects. The Hollanduses
particularly did their work in a spirit of thoroughly frank, original
investigation. They were more interested in minerals than in any other
class of substances, but did not waste much time on the question of
transmutation of metals. Professor Thompson, the professor of
chemistry at Edinburgh, said in his history of chemistry many years
ago that the Hollanduses ha