The Board of Longitude agreed with Mr William Wales and Mr William Bayley, to make astronomical observations; the former on board the Resolution, and the latter on board the Adventure. The great improvements which astronomy and navigation have met with from the many interesting observations they have made, would have done honour to any person whose reputation for mathematical knowledge was not so well known as theirs. The same Board furnished them with the best instruments, for making both astronomical and nautical observations and experiments; and likewise with four time-pieces, or watch machines; three made by Mr Arnold, and one made by Mr Kendal on Mr Harrison's principles. A particular account of the going of these watches, as also the astronomical and nautical observations made by the astronomers, has been before the public, by order of the Board of Longitude, under the inspection of Mr Wales. Besides the obligation I was under to this gentleman for communicating to me the observations he made, from time to time, during the voyage, I have since been indebted to him for the perusal of his journal, with leave to take from it whatever I thought might contribute to the improvement of this work. For the convenience of the generality of readers, I have reduced the time from the nautical to the civil computation, so that whenever the terms A.M. and P.M. are used, the former signifies the forenoon, and the latter the afternoon of the same day. In all the courses, bearings, &c., the variation of the compass is allowed, unless the contrary is expressed. And now it may be necessary to say, that, as I am on the point of sailing on a third expedition, I leave this account of my last voyage in the hands of some friends, who, in my absence, have kindly accepted the office of correcting the press for me; who are pleased to think that what I have here to relate is better to be given in my own words, than in the words of another person; especially as it is a work designed for information, and not merely for amusement; in which, it is their opinion, that candour and fidelity will counter-balance the want of ornament.