,
for the completion of his professional training, to the university
of Edinburgh, at that time illustrated and adorned by the genius and
learning of such men as the Monros, the Cullens, and the Blacks.

In pursuing his studies at this favoured abode of science and
literature, young Jackson is said to have evinced all that purity of
morals and singleness of heart which characterised him in
after-life, and to have resisted the allurements of dissipation by
which, in those days especially, the youthful student was tempted to
wander from the paths of virtuous industry. His circumstances were,
however, distressingly narrow; and not only was he forced to forego
the means of professional improvement open only to the more opulent
student; but in order to meet the expenses of the winter-sessions,
he was obliged to employ the summer, not in the study but in the
practice of his profession. He engaged himself as medical officer to
a Greenland whaler, and in two successive summers visited, in that
capacity, 'the thrilling regions of thick-ribbed ice;' returning on
each occasion with a recruited purse and a frame strengthened and
invigorated by exposure and exercise. During these expeditions he
occupied his leisure with the study of the Greek and Roman
languages, and the careful and repeated perusal of the best authors
in both.

His third winter-sessions at Edinburgh having passed away, he was
induced to go out and seek his fortune in Jamaica, and accordingly
proceeded thither in a vessel commanded by one Captain Cunningham,
who had previously been employed as master of a transport at the
siege of Havannah. It is far from improbable that it was from his
conversations with this individual that Jackson derived those hints,
of which at a future time he availed himself, respecting the
transmission of troops by sea without injury to their health; but it
is quite certain his conviction of the enormous value of cold-water
affusions as a curative agent in the last stage of febrile
affections, was imbibed from this source.

Arriving in Jamaica, he in 1774 became assistant to an eminent
general practitioner at Savana-la-Mar, Dr King, who was also in
medical charge of a detachment of the first battalion of the 60th
regiment. This latter he consigned to Jackson's care; and well
worthy of the trust did our young adventurer, though but twenty-four
years of age, approve himself--visiting three or four times a day
the quarters of the troops to