but in 1271 Gregory X came in on a conservative reaction. Bacon passed
most of the rest of his life in prison, perhaps through his own
ungovernable temper, and ostensibly his writings seem to have had little
or no effect on his contemporaries, yet it is certain that he was not an
isolated specimen of a type of intelligence which suddenly bloomed during
the Reformation. Bacon constantly spoke of his friends, but his friends
evidently did not share his temperament. The scientific man has seldom
relished martyrdom, and Galileo's experience as late as 1633 shows what
risks men of science ran who even indirectly attacked the vested interests
of the Church. After the middle of the thirteenth century the danger was
real enough to account for any degree of secretiveness, and a striking
case of this timidity is related by Bacon himself. No one knows even the
name of the man to whom Bacon referred as "Master Peter," but according to
Bacon, "Master Peter" was the greatest and most original genius of the
age, only he shunned publicity. The "Dominus experimentorum," as Bacon
called him, lived in a safe retreat and devoted himself to mathematics,
chemistry, and the mechanical arts with such success that, Bacon insisted,
he could by his inventions have aided Saint Louis in his crusade more than
his whole army. [Footnote: Emile Charles, _Roger Bacon. Sa vie et ses
ouvrages_, 17.] Nor is this assertion altogether fantastic. Bacon
understood the formula for gunpowder, and if Saint Louis had been provided
with even a poor explosive he might have taken Cairo; not to speak of the
terror which Greek fire always inspired. Saint Louis met his decisive
defeat in a naval battle fought in 1250, for the command of the Nile, by
which he drew supplies from Damietta, and he met it, according to Matthew
Paris, because his ships could not withstand Greek fire. Gunpowder, even
in a very simple form, might have changed the fate of the war.

Scepticism touching the value of relics as a means for controlling nature
was an effect of experiment, and, logically enough, scepticism advanced