It must not be omitted, that, while he occupied this post, he had an opportunity of exhibiting to the Royal Society a proof of his progress in the study of astronomy.

A short paper was written by him, and inserted in the fifty-seventh volume of the Philosophical Transactions, entitled, 'An Observation of an Eclipse of the Sun at the Island of Newfoundland, August 5, 1766, with the Longitude of the place of Observation deduced from it.' The observation was made at one of the Burgeo islands, near Cape Ray, in latitude 47 deg.

36' 19", on the south-west extremity of Newfoundland.

Mr.Cook's paper having been communicated by Dr.Bevis to Mr.Witchell, the latter gentleman compared it with an observation at Oxford, by the Rev.Mr.Hornsby, on the same eclipse, and thence computed the difference of longitude respecting the places of observation, making due allowance for the effect of parallax, and the prolate spheroidal figure of the earth.

It appears from the Transactions that our navigator had already obtained the character of being an able mathematician..