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 while the labours of his more scientific cotemporarycontemporary [sic], are in a great measure forgotten.

In 1810, the late Mr. Arrowsmith published “a Chart of the Dangers in the Channel between Sardinia, Sicily and Africa” formed from the original surveys of Captain D’Urban, viz. 1st. Of the Esquirques, two reefs of very large rocks, lying about two miles north and south of each other, surrounded by a bank of sand, the surface of which is chequered by patches of coral and large round stones of a bright red colour. 2d. Some dangers never before noticed, of a volcanic production, which he named Keith’s reef and shoal in compliment to his friend the late Viscount. 3d. A Survey of all the dangers on the N.W. coast of Sicily, between Trapani and Marsala, with the adjacent islands and channels of Favigana, Lavanso, Formiche, the rocks of Porcelli, &c.

The positions of the dangers here enumerated were determined by Captain D’Urban from the mean result of six chronometers; their rates having been carefully examined both previous to, and after the survey was finished. The soundings were taken in boats, and laid down from angles taken from vessels anchored on the shoals.

Agent.– Thomas Stilwell, Esq. 

 officer was made a Lieutenant in 1794; and on the 3d Sept., 1800, we find him commanding the Niger troop-ship, and leading her boats in conjunction with those of the Minotaur 74, to the attack of two Spanish corvettes, lying in the road of Barcelona, and reported to be destined for the relief of Malta, then blockaded by a British squadron.

The following is a copy of the official letter written by the late Sir Thomas Louis to Vice-Admiral Lord Keith, giving