COLBY, THOMAS, Major-General in the army, and one of the Directors of the Ordnance Survey, was born at Rochester 1st of Sep tember 1784. When his father, Captain Colby, of the Royal Marines, mailed with the fleet under Lord Howe, he was sent to Dr. Crockell's school at Xorthfleet, and from thence he entered the Royal Military Academy at Woolwich. Ile obtained his first commission as second lieutenant of engineers in 1801, being then but seventeen years of age. Ilia diligence and success in scientific 'Ludy were such that in January of the following year, at the special request of Captain Mudge, then superintendent of the ordnance survey, he was appointed one of the audatante hi that great work. Entering at once on his duties ho justified the expectations formed of him, by the intelligence and con scientious activity which he brought to the work of surveying. He was on a tour of inspection in Cornwall, in 1803, when he lost his left hand by the bunting of an old pistol, and suffered at the same time such a fracture of the skull from a fragment of the barrel, that he felt the effects' of the accident for the rest of his life whenever he attempted any long-continued mental exertion. Though the loss of his hand was • hindrance to the active discharge of his duties, Colonel Mudge was so well satisfied of his merits, that he kept the young lieutenant permanently attached to the survey.
In 1803 Lieutenant Colby was observing at Dunnose, one of the prominent points of the survey; in 1804 at Beaumaria; and iu 1806 with the zenith sector at Burleigh Moor and Dolma:ten Forest. The winter months he paned in the ' Drawing Room' at the Tower, computing and preparing the results for publication, and superin tending the construction and engraving of the ordnance maps on a scale of one inch to the mile. So thoroughly was he identified with that great national work, that the history of one becomes in great measure the history of the other. In 1807 Colby was promoted to the rank of captain. The third volume of An Account of the Trigo nometrical Survey of England' was published in 1811, and his name appearing jointly with that of Colonel Mudge on the title-page, showed how highly his services had been appreciated by his chief. In 1813 it was determined to extend the meridian line into Scotland, a task which called out in an especial manner the energies for which Captain Colby was remarkable. Within the next three years he visited and observed at the principal station+ beyond the Tweed, besides attending to his official business at the Tower. The persevering labour and
activity required for a season of observation on the hills would appear incredible to one unacquainted with the nature of the work. Beaidea the mental exercise of keeping all the subordinates to their duty, so as to produce harmony in the results, there was much personal fatigue to bo endured in long walks over the country, together with storms and wearisome delays on the mountain tops. But with Captain Colby duty was paramount, and he cared not for privation, so that the work was perfect. Major Dawson in his account of A Season on the Hills' gives a striking picture of the toils and hardships expe rienced : "It. was no uncommon occurrence," he remarks, "for the camp to be enveloped in clouds for several weeks together, without affording even a glimpse of the sun or of the clam sky during the whole period. And then in a moment the clouds would break away or subside into the valleys, leaving the tips of the mountains clear and bright above an ocean of mist, and the atmosphere calm and steady, so as to admit of the observations for which the party had waited days and weeks to bo taken in a few hours." At times the tents would be blown down by storms—or the camps would be whitened by a fall of bail or snow in July : or the captain taking two or three of the junior officers and a few men with him would start on a station-hunt ; ' steering a course direct by compass for the peaks that seemed most suitable, regardless of the nature of the intervening country. In these explorations they walked from thirty to forty miles a day, wading streams, crossing bogs, scaling cliffs, and sliding down into rocky valleys, Captain Colby ever the foremost; and when they came to a summit which his experience told him was suitable for a station, he would help with his own hand in building up the great pile of stones by which it was to be distinguished and observed from distant points. Sometimes the resting-place at night would be a miserable hovel where no other food was to be obtained than the national porridge; at others the weary explorers rested under a ducal roof—and on the west coast during the hot months they were tormented and blistered by the bites of innumerable midges. iu one trip in 1819 the party walked 586 miles in twenty-two days. From this brief summary, a notion may be formed of the severe labour of the survey, apart from the scientific duty of observing with the instruments, which on all favourable occasions was continued from sunrise to sunset.