DRUMMOND, CAPTAIN THOMAS, was born at Edinburgh, in October 1797, the second of three Ions. Ilia father died whilst he was an Infant; 1114 mother removed to Musselburgh, where she resided many years, devoting herself entirely to the education of her children. Drummond was early entered at the High School of Edinburgh, and there formed an acquaintance with Professors Mayfair, Leslie, and Browder, and also with Professors Wallace and Jardine, whose pupil he more especially was. In February 1913 he was appointed to a cadetehlp at 1Voolwich. Ills mathematical abilities soon made him conspicuous, and he paned with very unusual rapidity through all the grades of the academy. Much of his success was doubtless to be attributed to the admirable preliminary education he had received, but much also to a character of determined perseverance, and to the vigorous and well-regulated mind he brought to bear on nli subjects. To this it was probably duo that he never became exclusively a mathematician, but advanced equally in all the various branches of Rudy, being at that time, u he continued through life, distinguished for general knowledge and for aptitude to seize on information of every kind. His friend and master, Professor Barlow, notices a cir etimatance which will illustrate his character: "While a cadet in a lunior academy (at Woolwich), not being satisfied with a rather difficult demonstration in tho conio sections, ho supplied one himself on an entirely original principle, which at the time was published iu Leybourne's ' Mathematical Repository,' and was aubsequently taken to replace that given in Dr. Hutton's ' Course of Mathematics,' to which he had objected. This apparently trifling event gave an increased stimulus to his exertions, and may perhaps be considered the foundation stone of his future ecientiflo fame. After leaving the academy ho still continued his intercourse with his mathematical wasters, with whom ho formed a friendship which only terminated in his much lamented death." During his preliminary and practical instruction in the special duties of the Engineering Department, his talent for mechanical combinations became conspicuous, and a pontoon which he invented was particularly admired as suitable to ite immediate purpose, and remarkably easy of transport, while according to his contemporary and friend, Captain Dawson, to whose information this notice is largely indebted, csch section into which it was cut for facility of transport, as well as to prevent it from sinking if injured in any one part, was said by the dockyard-men to whom he showed it, to be easier to row than any boat except a gig. This early period of his career was also
largely devoted to the acquisition of military knowledge, partly from the associations around him, and partly from the circumstances of the times. Jomini and Boustnard were his favourite authors, aud often has the morning tight surprised him in deep discussion ou the details of Waterloo and the strategy of the recent campaigns. At Chatham, the practical and varied applications of scientific knowledge brought by Colonel (now General) Feeley to the aid of military science, offered the highest attractions to a mind like Drummoud's. Before he joined at Chatham he had served a short time at Plymouth, and after hie Chatham course was completed he was stationed at Edinburgh. The duties there offered nothing to engage his attention, relating merely to the charge and repairs of publio works ; but he was happy in being again thrown among his family and friends, and more in the opportunity again afforded him of .pursuing the higher studies in which he delighted, at the college and classes, and among the scientific society of his native city. He found the duties how ever so trivial, and the prospects of the service so disheartening, that for some time ho meditated leaving the army for the bar, and had actually entered his name at Lincolu's Inn with this view. But in the autumn of ]819 ho fortunately became acquainted with Colonel Colby, when that officer was passing through Edinburgh ou his return from the trigonometrical operations in the Scottish Highlands. The opportunity which these duties afforded him of combining scientific pursuits with the military service induced him to abandon his intention of forsaking the corps, and in the course of the following year an offer from Colonel Colby to take part in the trigonometrical survey was gladly accepted. Ile had now the advantage of a residence during each winter in London, and, with a definite object in view, again devoted himself, and more closely than over, to the study of the higher branches of mathematics.