ing observations upon the immersions and emersions of Jupiter's satellites,
which he forwarded to the Greenwich Observatory. About the same period,
he constructed a chart of the Straits of Alias, and sent it, with other smaller
surveys, to Mr. Dalrymple, by whom they were engraved.
It was now full time that Captain Horsburgh should abandon his precarious profession, which he had learned so thoroughly, and turn his useful acquirements to their proper account. It was too much that the life of one upon whose future labours the safety of whole navies was to depend, should be exposed to the whiff of every sudden gale, or the chance starting of a timber. Already, also, he had completed for publication a large collection of charts, accompanied with explanatory memoirs of the voyages from which they had been constructed, and these, with his wonted disinterestedness, he was about to transmit to his predecessor, Mr. Dalrymple. Fortunately, Sir Charles Forbes interposed, and advised him to carry them home, and publish them on his own account; and as Horsburgh was startled at the idea of the expense of such a venture in authorship, his whole savings amounting by this time to no more than 5000 or 6000, the great Indian financier soon laid his anxieties to rest, by procuring such a number of subscribers for the work in India as would more than cover the cost of publishing. Thus cheered in his prospects, Captain Horsburgh returned to England in 1805, and forthwith commenced his important publication, from which his memory was to derive such distinction, and the world such substantial benefit. So correct were these charts, that even this very correctness, the best and most essential quality of such productions, threatened to prevent their publication; for with such accuracy and minuteness were the bearings and soundings of the harbour of Bombay laid down, that it was alleged they would teach an enemy to find the way in without the aid of a pilot. It was no wonder, indeed, that these were so exact; for he had taken them with his own hands, during whole weeks, in which he worked from morning till night under the fire of a tropical sun. In the same year that he returned to England, he married, and had by this union a son and two daughters, who survived him. In 1806 he was elected a fellow of the Royal Society; and in 1810 he was appointed hydrographer to the East India Company, by the Court of Directors, on the death of Mr. Dalrymple. Just before this appointment, however, he published his most important work, entitled "Directions for Sailing to and from the East Indies, China, New Holland, the Cape of Good Hope, and the interjacent ports." These "Directions," undertaken at the request of several navigators of the eastern seas, and compiled from his journals and observations during twenty-one years, have ever since continued to be the standard and text-book of eastern ocean navigation.
On being appointed hydrographer to the East India Company, Mr. Horsburgh devoted himself, with all his wonted application, to the duties of his office. He constructed many new charts, the last of which was one of the east coast of China, with the names of the places in Chinese and English; and published an "Atmospherical Register" for indicating storms at sea, besides editing Mackenzie's "Treatise on Marine Surveying," and the "East India Pilot." From 1810, the year of his appointment, till 1836, the year of his death, he was indefatigable in that great work of humanity to which he may be said to have ultimately fallen a martyr for his long-continued labours among the scientific documents contained in the cold vaults and crypts of the India House, and his close attention to the countless minutiae of which the science of hydrography is
