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A few years before the transit of 1761, Delisle, the French astronomer, undertook a careful analysis of all the circumstances of the approaching phenomenon. It had been ascertained that the transit of 1761 was only the first of a pair of transits, the second occurring in 1769; and it was found that the method by which Halley had proposed to utilize the earlier transit would not, on this occasion, be altogether suitable. I shall presently describe the methods respectively suggested, but it is necessary to mention them here, in order that the chronological sequence of the events may be recognized. For many who have heard Delisle's method lately spoken of and insisted upon (as in Parliament by Mr. Goschen) have been led to imagine that it is a recent invention, and, again, that it possesses great advantages over Halley's, whereas it was known and discussed before the transits of 1761 and 1769, and, while very properly adopted for the first transit, was as properly superseded by Halley's in the case of the second.

The transit of 1761 (like that which will occur on December 6, 1882) was partially visible in England. It was observed at Greenwich by the Rev. M. Bliss, Astronomer Royal, and at Savile House, near London, by Mr. Short, "in presence," says the account, "of his Royal Highness the Duke of York, accompanied by their Royal Highnesses Prince William, Prince Henry, and Prince Frederick." A great number of observations were made also in different parts of the world, and a sufficiently satisfactory determination of the sun's distance was deduced therefrom.

It was, however, in 1769, that the real attack was made. It was then that the famous expedition of Captain Cook, in the Endeavor, was made, England being the only country which had a station in the Pacific. The arctic regions were visited also, a station being selected at Wardhus, in North Lapland, where the following notable