elasticity (was condensed into water vapors). The cock was then
again opened so as to let in more of the same air to supply the
place of that destroyed by the explosion, which was again fired,
and the operation continued till almost the whole of the mixture
was let into the globe and exploded. By this means, though the
globe held not more than a sixth part of the mixture, almost the
whole of it was exploded therein without any fresh exhaustion of
the globe."

At first this condensed matter was "acid to the taste and
contained two grains of nitre," but Cavendish, suspecting that
this was due to impurities, tried another experiment that proved
conclusively that his opinions were correct. "I therefore made
another experiment," he says, "with some more of the same air
from plants in which the proportion of inflammable air was
greater, so that the burnt air was almost completely
phlogisticated, its standard being one-tenth. The condensed
liquor was then not at all acid, but seemed pure water."

From these experiments he concludes "that when a mixture of
inflammable and dephlogisticated air is exploded, in such
proportions that the burnt air is not much phlogisticated, the
condensed liquor contains a little acid which is always of the
nitrous kind, whatever substance the dephlogisticated air is
procured from; but if the proportion be such that the burnt air
is almost entirely phlogisticated, the condensed liquor is not at
all acid, but seems pure water, without any addition
whatever."[2]

These same experiments, which were undertaken to discover the