Life and Scientific Work of Peter Guthrie Tait - School of Mathematics ...

ORDINARY CLASS LECTURES 19
to the thermo-dynamic discoveries of Kelvin. His passage at arms with
Herbert Spencer Tait himself never regarded as anything else than a
big joke.
As a lecturer Tait was probably unsurpassed by any of his con-
temporaries. His lecture notes were merely jottings of headings with the
experiments indicated and important numerical values interspersed. In the
original note book, which was in use till 1881, these headings were entered
with intervening spaces so as to allow for additions as time went on.
In 1 88 1 he rewrote the greater part of the notes in a smaller octavo
book, and this he continued to use to the end.
These lecture notes had to do with the properties of matter, which
largely occupied
the attention of the class for the first half of the winter
session. Tait regarded this part of the course as a general introduction
to the study of Natural Philosophy. He devoted the first few days to a
discussion of the nature of the subject and of the means by which we gain
knowledge of the physical universe. His treatment of the subjective and
objective from the point of view of the natural philosopher was always clear
and reasonable. I remember going back with a former classmate to hear
Tait's opening lecture. Since we had first sat together in the benches of
the Natural Philosophy Class room my friend had pondered deeply
physical themes ;
on meta-
and, as we listened again to Tait's exposition of objective
and subjective, he whispered to me " Beautiful, Berkeley couldn't have done
it better."
The conceptions of time and space, and the realities known as matter
and energy, were introduced and placed in their right setting from the
physical standpoint. These preliminaries disposed of, Tait began his systematic
lectures on the properties of matter. His aim was to build a truly
philosophical body of connected truths upon the familiar experiences of the
race. In ordered sequence the various obvious properties of matter were
considered, first, in themselves, then in their theoretical setting and their
practical applications. Thus, to take but one example, the discussion of the
divisibility of matter led to the consideration of mechanical sub-division and of
the elementary principles of the diffraction and interference of light, illustrated
by colours of soap films, halos and supernumerary rainbows. The fuller
explanation of these was, however, reserved for a later date when the laws
of physical optics were taken up in more detail. In this way the intelligent
student was able during the first two months to gain a general outlook upon
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