James Gregory (1638-1675)
Gregorian Reflecting Telescope,1736
Signed: James Short Edinburh 1736. 1/82
Short (1710-68) was a self taught artisan of tremendous skill and made over 1300 telescopes during his lifetime.
This telescope was his 82nd creation and the first to made in this size.
Brass and tin, with ivory adjustment tabs. Height 49cm, length 86cm.
James Gregory, the Aberdeen
mathematician, is arguably the greatest scientist associated with St Andrews.
In 1661, at the age of 23, he invented a type of reflecting telescope, later to
be described as `Gregorian'. He was appointed to the newly established Chair of
Mathematics at St Andrews in 1668 and almost immediately began to plan an
observatory. In 1673 he was authorised by the University to go to London
specifically to purchase `. . . such instruments and utensils as he with advice
of other skilful persons shall judge most necessary and useful.' His purchases
included three clocks, made by the leading London clock maker, Joseph Knibb - a
matched pair of long-case clocks and a smaller split-second timepiece (the
first such instrument ever produced), which are still in the possession of
the University. Gregory described these clocks in a letter dated 19th July,
1673 from Gregory to John Flamsteed, the first Astronomer Royal at Greenwich.
Another letter of 1674 mentions that other instruments were acquired, and these
may well have included the great planispheric astrolabe and armillary sphere
made by the Elizabethian engraver Humphery Cole, and the mariner's astrolabe of
Elias Allen. Support for the connection between Gregory and the Elizabethian
instruments is provided by the fact that the great planispheric astrolabe has a
plate which was produced specially for it by John Marke, a London instrument
maker of Gregory's period, which enables the astrolabe to be used at a Scottish
latitude.
Gregory was a friend of John Collins, a leading London mathematician, who had
studied at Cambridge and kept him abreast of recent discoveries. Gregory may
possibly have visited Isaac Newton at Cambridge, as the more famous
mathematician frequently relied upon Gregory's work in subsequent years. Indeed
the pair were often working on very similar projects at almost identical times.
In 1667, for example, Gregory developed converging series to obtain
quadratures, a process later used by Newton, who remarked: "The same year I
found the methods of tangents of Gregory. . . and in November had the direct
method of fluxions!"
However, after initial enthusiasm, the St Andrews academics found Gregory's
`New Philosophy' distasteful: `a prejudice which the Masters of the University
did take at Mathematics' (Gregory's own words) led to violence as students were
forcibly kept from his lectures. In 1674 Gregory accepted an invitation to
become a professor at Edinburgh University, but died the following year, aged,
37. A member of an incredibly illustrious scientific family, Gregory's
contribution to the field of mathematics and natural philosophy was immense.
Indeed he is unlikely to be forgotten, as telescopes made to his design will
forever carry his name.
9 May 1996
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