XX. Letter from Captain Basil Hall, R. N. to Captain Kater, communicating the details of experiments made by him and Mr. Henry Foster, with an invariable pendulum; in London; at the Galapagos Islands in the Pacific Ocean, near the Equator; at San Blas de California on the N. W. Coast of Mexico; and at Rio de Janeiro in Brazil. With

Abstract

My Dear Sir, I herewith transmit the details of the experiments which have been made with the invariable pendulum, placed in my hands by the Board of Longitude, at your suggestion. It is matter of regret to me, that I should have visited so many remote places, with such means in my hands, and have so few results to produce. The fact however is, that the ser­vice upon which I was sent had no connection with scientific research, and that it was only at casual intervals of active professional employment, that I had any leisure for enquiries of this nature. These occasional opportunies I owe to the generous indulgence of Sir Thomas Hardy, the Commander in Chief, to whose assistance, also, and encouragement in every pursuit having useful knowledge for its object, I stand essentially indebted.