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SINCLAIR, GEORGE, a well-known mathematical writer, was
professor of philosophy in the university of Glasgow in the latter part of
the seventeenth century. No particulars of his early life have been
ascertained. He was admitted a professor of Glasgow university, April 18,
1654, [Records of the University.] and was ejected in 1662, for declining to
comply with the episcopal form of church government, then thrust upon the
people of Scotland. He had, in the previous year, published at Glasgow, his
first known work, "Tyrocinia mathematica, in novem tractatus, viz.,
mathematicum, sphericum, geographicum, et echometricum, divisa," l2mo. After
his ejection, he betook himself to the business of a mineral surveyor and
practical engineer, and was employed in that profession by several
proprietors of mines in the southern parts of Scotland, and particularly by
Sir James Hope, who, having sat in Barebones’ parliament, was probably
nowise averse to his presbyterian principles. In 1669, he published at
Rotterdam, "Ars Nova et Magna Gravitatis et Levitatis," 4to. He was employed
by the magistrates of Edinburgh, about 1670, to superintend the introduction
of water from Cormiston into the city; a convenience with which the capital
of Scotland had not previously been furnished. Considerable attention seems
to have been paid by him to such branches of hydrostatics as were of a
practical nature; and it has been said that he was the first person who
suggested the proper method of draining the water from the numerous coal
mines in the southwest of Scotland. In 1672, he published at Edinburgh a
quarto entitled, "Hydrostaticks; or, the Force, Weight, and Pressure of
Fluid Bodies, made evident by physical and sensible Experiments, together
with some Miscellany Observations, the last whereof is a short history of
Coal." And, in 1680, he published at the same place, in 8vo, what appears to
have been a modification of the same work, "Hydrostatical Experiments, with
Miscellany Observations, and a relation of an Evil Spirit; also a Discourse
concerning Coal." Sinclair’s writings, in the opinion of a very able judge,
are not destitute of ingenuity and research, though they may contain some
erroneous and eccentric views. The work last named contained a rather
strange accompaniment to a scientific treatise,—an account of the witches of
Glenluce,—which, if there had been no other evidence of the fact, shows the
author to have not been elevated by his acquaintance with the exact sciences
above the vulgar delusions of his age. It must be recollected, however, that
other learned men of that age were guilty of like follies. The
self-complacency of Sinclair, and his presbyterian principles provoked the
celebrated James Gregory, then a professor at St Andrews, to attack his
Hydrostatics in a pamphlet published with the quaint title of the "Art of
Weighing Vanity," and under the thin disguise of Patrick Mather, archbeadle
of the university of St Andrews. It is curious to observe that with all his
eagerness to heap ridicule on his antagonist, Gregory never once touches on
what would now appear the most vulnerable point, the episode about the
witches. After a long interval, Sinclair wrote an answer to Gregory,
entitled, "Cacus pulled out of his den by the heels, or the pamphlet
entitled, the New and Great Art of Weighing Vanity examined, and found to be
a New and Great Act of Vanity." But this production was never published: it
remains in manuscript in the university library at Glasgow, to which the
author appears, from an inscription, to have presented it in 1692. Sinclair
was among the first in Britain who attempted to measure the heights of
mountains by the barometer. It is said that Hartfell, near Moffat, was the
first hill in Scotland of which the height was thus ascertained. In the
years 1668 and 1670, he observed the altitudes of Arthur’s Seat, Leadhills,
and Tinto, above the adjacent plains. He followed the original mode of
carrying a sealed tube to the top of the mountain, where, filling it
with quicksilver, and inverting it in a basin, he marked the elevation of
the suspended column, and repeated the same experiment below; a very rude
method, certainly,—but no better was practised in England for more than
thirty years afterwards. To the instrument fitted up in a frame, Sinclair
first gave the name baroscope, or indicator of weight; a term
afterwards changed for barometer, or measurer of weight. In
these rude attempts at measuring weights by the mercurial column, the
atmosphere was regarded simply as an homogeneous fluid, and possessing the
same density throughout its whole mass; a supposition, which, it is needless
to point out, must have led the observer wide of the truth, where the
elevation was considerable.
The work by which Sinclair is
now best remembered is his "Satan’s Invisible Works Discovered," which was
published about the year 1685, and has since been frequently reprinted. This
is a treatise on witches, ghosts, and diablerie, full of instances ancient
and modern, and altogether forming a curious record of the popular notions
on those subjects at the period when it appeared: it was for a long time a
constituent part of every cottage library in Scotland. In Lee’s Memorials
for Bible Societies in Scotland, is given the following decree of the Privy
Council, in favour of Mr Sinclair’s copyright in this precious production: "Apud
Edinburgh, 26 Feb., 1685. The lords of his majesties privy councill
considered ane address made to them by Mr George Sinclair, late professor of
philosophie at the colledge of Glasgow, and author of the book entitled
‘Satan’s Invisible Works Discovered,’ &c., doe hereby prohibite and
discharge all persons whatsomever from printing, reprinting, or importing
into the kingdome any copy or copies of the said book during the space of
eleven zearis after the date hereof without licence of the author or his
order, under the pain of confiscation thereof to the said author, besydes
what further punishment we shall think fitt to inflict upon the
contraveeners." The first edition contains a very curious dedication to the
earl of Winton, not to be found in the rest, but which has been lately
republished in the "Historie of the Hous and Name of Setoun," printed by the
Maitland Club.
It is curious to find science
and superstition so intimately mingled in the life of this extraordinary
person. In 1688, he published at Edinburgh, in 12mo, the "Principles of
Astronomy and Navigation." The only other publication attributed to him is a
translation of David Dickson’s "Truth’s Victory over Error." It is hardly
possible to censure delusions which seem to have been entertained with so
much sincerity, and in company with such a zeal for the propagation of real
knowledge.
Mr Sinclair was recalled at
the Revolution to the charge from which he was expelled twenty-six years
before. On the 3rd of March, 1691, the faculty of the college revived the
professorship of mathematics, which had been suppressed for want of funds;
and at the same time appointed Mr Sinclair to that chair. He died in 1696. |
