production of the elastic particles we are considering. For no
art or curious instruments are required to make these shavings
whose curls are in no wise uniform, but seemingly casual; and
what is more remarkable, bodies that before seemed unelastic, as
beams and blocks, will afford them."[1]

Although this explanation of the composition of the air is most
crude, it had the effect of directing attention to the fact that
the atmosphere is not "mere nothingness," but a "something" with
a definite composition, and this served as a good foundation for
future investigations. To be sure, Boyle was neither the first
nor the only chemist who had suspected that the air was a mixture
of gases, and not a simple one, and that only certain of these
gases take part in the process of calcination. Jean Rey, a
French physician, and John Mayow, an Englishman, had preformed
experiments which showed conclusively that the air was not a
simple substance; but Boyle's work was better known, and in its
effect probably more important. But with all Boyle's explanations
of the composition of air, he still believed that there was an
inexplicable something, a "vital substance," which he was unable
to fathom, and which later became the basis of Stahl's phlogiston
theory. Commenting on this mysterious substance, Boyle says:
"The, difficulty we find in keeping flame and fire alive, though
but for a little time, without air, renders it suspicious that
there be dispersed through the rest of the atmosphere some odd
substance, either of a solar, astral, or other foreign nature; on
account of which the air is so necessary to the substance of
flame!" It was this idea that attracted the attention of George
Ernst Stahl (1660-1734), a professor of medicine in the
University of Halle, who later founded his new theory upon it.