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DRUMMOND, CAPTAIN
THOMAS.—Among the many distinguished engineers of whom Scotland has been
so prolific in the present age, the subject of this notice will always
hold a conspicuous place. He was born at Edinburgh, in October, 1797, and
was the second of three sons; and being deprived of his father while still
in infancy, the care of his education devolved upon his mother, who
discharged her duty in that respect so effectually that the Captain ever
afterwards spoke of her with affectionate gratitude, and attributed much
of his professional success to her careful and efficient training. After
having undergone the usual course of a classical education at the High
School of Edinburgh, he was entered at Woolwich as a cadet in 1813; and
such was the persevering energy and diligence with which his home-training
had inspired him, that he soon distanced his school-fellows, and passed
through the successive steps of the military college with a rapidity
altogether unusual in that institution. It was not in mathematics alone,
also, that he excelled, but in every other department of science to which
he turned his attention; for such was his intellectual tenacity and power
of applications, that he never relinquished a subject until he had
completely mastered it. Of this he once afforded a striking proof while
still in one of the junior academies of the college. Not being satisfied
with a difficult demonstration in conic sections contained in Hutton’s
"Course of Mathematics," which formed the text-book of the class, young
Drummond sought and discovered a solution of a more simple character, and
on a wholly original principle. Such was the merit of this bold
innovation, that it replaced the solution of Hutton among the professors
of Woolwich College, who were proud of their young pupil, and entertained
the highest hopes of his future success as a military engineer. The same
reflective independent spirit characterized his studies after he had left
Woolwich to follow out the practical instruction of his profession. On one
occasion his attention was directed to the various inventions by which the
use of the old pontoon was to be superseded; and he contrived a model,
which was reckoned a master-piece of ingenuity. It was, says his friend
Captain Dawson, who describes it, "like a man-of-war’s gig or galley,
sharp at both ends, and cut transverely into sections, for facility of
transport, as well as to prevent it from sinking if injured in any one
part; each section was perfect in itself, and they admitted of being
bolted together, the partitions falling under the thwarts or seats. The
dockyard men, to whom he showed it, said it would row better than any boat
except a gig; and it was light, and capable of being transported from
place to place on horseback."
After having spent some
time in training, both at Plymouth and Chatham, during which he embraced
every opportunity of improving his professional knowledge, not only by
books and the conversation of intelligent officers and scientific
scholars, but also by a visit to France, to study its army of occupation
and witness a great military review, Drummond was stationed at Edinburgh,
where his charge consisted in the superintendence and repair of public
works. But this sphere was too limited for his active spirit; and, finding
little prospect of advancement in his profession, he had serious thoughts
of abandoning it for the bar, and had actually enrolled his name as a
student at Lincoln’s Inn, when fortunately, in the autumn of 1819, he met
in Edinburgh with Colonel Colby, at that time engaged in the
trigonometrical survey of the Highlands. Delighted to have such an
associate in his labours, the colonel soon induced the disappointed
engineer to abandon all further thoughts of the study of law, and join him
in the survey. As these new duties required Drummond to reside in London
during the winter, he availed himself of the opportunity not only to
improve himself in the higher departments of mathematics, but also to
study the science of chemistry, which he did with his wonted energy and
success. While attending, for this purpose, the lectures of Professors
Faraday and Brande, his attention was called to the subject of the
incandescence of lime; and conceiving that this might be made available
for his own profession, he purchased, on his return from the lecture-room,
a blow-pipe, charcoal, and other necessary apparatus, and commenced his
course of experiments. These were prosecuted evening after evening, until
he had attained the desired result. He found that the light derived from
the prepared lime was more brilliant than that of the Argand lamp; and
that it concentrated the rays more closely towards the focal point of the
parabolic mirror, by which they were reflected in close parallel rays,
instead of a few near the focus, as was the case with the Argands.
An opportunity was soon
given to test this important discovery. In 1824, Colonel Colby was
appointed to make a survey of Ireland, and took with him Lieutenant
Drummond as his principal assistant. The misty atmosphere of Ireland made
this survey a work of peculiar difficulty, as distant objects would often
be imperceptibly seen under the old system of lighting; but the Colonel
was also aware of the improved lamp which Drummond had invented, and
sanguine as to its results. His hopes were justified by a striking
experiment. A station called Slieve Snaught, in Donegal, had long been
looked for in vain from Davis’ Mountain, near Belfast, about sixty-six
miles distant, with the haze of Lough Neagh lying between. To overcome
this difficulty, Drummond repaired to Slieve Snaught, accompanied by a
small party, and taking with him one of his lamps. The night on which the
experiment was made was dark but cloudless, and the mountain covered with
snow, when the shivering surveyors left their cold encampment to make the
decisive trial. The hour had been fixed, and an Argand lamp had been
placed on an intermediate church tower, to telegraph the appearance of the
light on Slieve Snaught to those on Davis’ Mountain. The hour had past,
and the sentry was about to leave his post, when the light suddenly burst
out like a brilliant star from the top of the hitherto invisible peak, to
the delight of the astonished spectators, who were watching with intense
anxiety from the other station of survey. Another invention of almost
equal importance with the Drummond’s light was his heliostat, by which the
difficulty arising from the rapid motion of the earth in its orbit round
the sun, was obviated by the most simple means, and the work of survey
made no longer dependent upon a complicated apparatus that required
frequent shifting and removal; so that, while it could take observations
at the distance of a hundred miles, a single soldier was sufficient to
carry and plant the instrument upon the requisite spot.
The high scientific
knowledge which Drummond possessed, and the valuable services he had
rendered to the Irish survey, were not lost sight of, and demands soon
occurred to call him into a higher sphere of duty. These were, the
preparations necessary before the passing of the Reform Bill, by laying
down the boundaries to the old and the new boroughs. This very difficult
task he discharged so ably, and so much to the satisfaction of the public,
as to silence the murmurs of cavillers, who complained because a young
lieutenant of engineers had been appointed to so important a charge. After
it was finished, he returned to his work of surveying; but in the midst of
it was appointed private secretary to Lord Spencer, in which office he
continued till the dissolution of the government, when he was rewarded
with a pension of £300 per annum, obtained for him through the interest of
Lord Brougham. In 1835, he was appointed undersecretary for Ireland, where
he was placed at the head of the commission on railways; but his incessant
labour in this department, along with his other duties of a political
nature, are supposed to have accelerated his death, which occurred April
15, 1840. His memory will continue to be affectionately cherished, not
only by the distinguished statesmen with whom he acted, but by society at
large; while the scientific will regret that public duties should have
latterly engrossed a mind so admirably fitted for the silent walks of
invention and discovery. |
