ave seen the great man coming from his rooms {116a} in the N.E.
corner of the Great Court of Trinity--that corner where Newton's and
other more modern ghosts surely walk--Macaulay who used to read, pacing
to and fro by the chapel, {116b} and Thackeray who, like his own Esmond,
lived "near to the famous Mr. Newton's lodgings." In any case there can
be no doubt that the genius of Newton cast its light on Hales, as Sachs
has clearly pointed out (_Hist. Bot._, Eng. Tr., p. 477). Another great
man influenced Hales, namely Robert Boyle, who was born 1627 and died
1691. John Mayow again, that brilliant son of Oxford, whose premature
death at 39 in 1679 was so heavy a blow to science, belongs to the same
school as Hales--the school which was within an ace of founding a
rational chemistry, but which was separated from the more obvious
founders of that science by the phlogiston-theory of Becchers and Stahl.
I do not find any evidence that Hales was influenced by the phlogistic
writers, and this is comprehensible enough, if, as I think, he belongs to
the school of Mayow and Boyle.

The later discoverers in chemistry are of the following dates, Black
1728-1799, Cavendish 1731-1810, Priestley 1733-1804, Scheele 1742-1786,
Lavoisier 1743, guillotined 1794. These were all born about the time of
Hales' zenith, nor did he live {117} to see the great results they
accomplished. But it should not be forgotten that Hales' chemical work
made more easy the triumphant road they trod.

I have spoken of Hales in relation to chemists and physicists because,
though essentially a physiologist, he seems to me to have been a chemist
and physicist who turned his knowledge to the study of life, rather than
a physiologist who had some chemical knowledge.

Whewell points out in his _History of the Inductive __Sciences_ {118a}
that the physiologist asks questions of Nature in a sense differing from
that of the physicist. The _Why_? of the physicist meant _Through what
causes_? that of the physiologist--_to what end_? This distinction no
longer holds good, and if it is to be applied to Hales it is a test which
shows him to be a physicist. For, as Sachs shows, though Hales was
necessarily a teleologist in the theological sense, he always asked for
purely mechanical explanations. He was the most unvitalistic of
physiologists, and I think his explanations suffered from this cause.
For instance, he seems to have held that to compare the effect of hea