From Madras Colebrooke proceeded, in 1783, to Calcutta, where he met his elder brother, already established in the service. His own start in official life was delayed, and took place under circumstances by no means auspicious. The tone, both in political and private life, was at that time at its lowest ebb in India. Drinking, gambling, and extravagance of all kinds were tolerated even in the best society, and Colebrooke could not entirely escape the evil effects of the moral atmosphere in which he had to live. It is all the more remarkable that his taste for work never deserted him, and “that he would retire to his midnight Sanskrit studies unaffected by the excitement of the gambling-table.” It was not till 1786--a year after Warren Hastings had left India--that he received his first official appointment, as Assistant Collector of Revenue in Tirhut. His father seems to have advised him from the first to be assiduous in acquiring the vernacular languages, and we find him at an early period of his Indian career thus writing on this subject: “The one, and that the most necessary, Moors (now called Hindustani), by not being written, bars all close application; the other, Persian, is too dry to entice, and is so seldom of any use, that I seek its acquisition very leisurely.” He asked his father in turn to send him the Greek and Latin classics, evidently intending to carry on his old favorite studies, rather than begin a new career as an Oriental scholar. For a time he seemed, indeed, deeply disappointed with his life in India, and his prospects were anything but encouraging. But although he seriously thought of throwing up his position and returning to England, he was busy nevertheless in elaborating a scheme for the better regulation of the Indian service. His chief idea was, that the three functions of the civil service--the commercial, the revenue, and the diplomatic--should be separated; that each branch should be presided over by an independent board, and that those who had qualified themselves for one branch should not be transferred to another. Curiously enough, he lived to prove by his own example the applicability of the old system, being himself transferred from the revenue department to a judgeship, then employed on an important diplomatic mission, and lastly raised to a seat in Council, and acquitting himself well in each of these different employments. After a time his discontent seems to have vanished. He quietly settled down to his work in collecting the revenue of Tirhut; and his official duties soon became so absorbing, that he found little time for projecting reforms of the Indian Civil Service.