604 MEMOIR OF SIR THOMAS MAKDOUGALL BRISBANE. 
Our first triumphs in those fair climes have been the peaceful ones of science ; 
and the treasures they have transmitted to us are imperishable records of 
useful knowledge, speedily to be returned with interest to the improvement of 
their condition, and their elevation in the scale of nations.” 
Since this beautiful address was delivered by Sir JoHn HERSCHEL, the ob- 
servations made at Parramatta of Encoxr’s comet have formed the basis— 
and a solid one—for the most sublime speculations of the astronomers of our 
time. This remarkable body performs its revolution round the sun in 34 years, 
and has been observed to complete its rotation in a constantly decreasing 
period, verging year by year nearer to the sun. From this fact, astronomers 
have concluded, that all the planets are moving in a thin, attenuated, but yet 
resisting medium, and that our earth, and all its associates, are winding through 
a long spiral orbit towards the sun, and must fall at last into its burning 
atmosphere. 
On his return from Australia, Sir Tuomas resided chiefly at Makerstoun, 
where he established an astronomical observatory surpassing any other in Scot- 
land at the time; the equatorial alone, by TRoucHTON and Sims, having cost him 
upwards of £600. 
When the British Association undertook the question of the laws of the 
earth’s magnetism, Sir THomAs joined most zealously in the cause; and had it 
not been for his almost princely munificence, Scotland would have been left 
unrepresented in the great congress of magnetic inquiry. In 1841 he estab- 
lished his magnetic observatory at Makerstoun, certainly not inferior to any in 
Europe. With the assistance of a very able staff of assistants, of whom Mr 
ALLAN Broun (now astronomer to the Rajah of Travancore) was director, he sent 
forth three large volumes of Observations, which were published at the joint 
expense of this Society and Sir Tuomas, and for which he was awarded the 
highest honour in their gift, the Keith Medal. Principal Forses has well said of 
these works, that ‘‘they form probably the greatest contribution made to science 
by Sir Tuomas BrissAnE—hardly even excepting the establishment of the Aus- 
tralian observatory. They have a double interest for us, as being a unique 
contribution to the science of his native country; and he was liberally anxious 
that the Royal Society should be so far associated with him in this truly 
patriotic work.” 
Whilst resident at Makerstoun he was offered the command of the troops in 
Canada, and shortly afterwards the chief command in India, but the advice of 
his medical friends constrained him to decline both of these honourable pre- 
ferments. On the death of Sir WaLtTErR Scort in 1833, he was elected President 
of this Society, and showed his high appreciation of the honour by the deep 
interest he always took in its welfare, and lastly, by founding the Brisbane 
Biennial Medal for scientific merit. 
