In conclusion, I have to return my thanks to the former President, the Lord Wrottesley, to the Council, and Officers of the Royal Society, and more particularly to my much-respected friend General Sabine, then Treasurer and now President, for that assistance and co-operation, from the outset, without which this investigation could never have been accomplished.
To my distinguished friends. Sir Roderick I. Murchison, Bart., and Sir Charles Lyell, for their assistance in laying the objects of the proposed expedition before the Council of the Royal Society, and for valuable letters to influential persons abroad. To Cardinal Wiseman for his most useful encyclical letter; and to the Lords of the Admiralty for chronometers placed at my disposal.
To several friends resident at Naples, both English and Italian, I am indebted for advice and assistance, not the less important because too multifarious to specify, but to none more than to Signor Guiscuardi.
Most of all, however, are my thanks personally due to my friend Dr. Thomas Romney Robinson, Astronomer, of Armagh, the weight of whose authority gave the first impulse to my expedition; to Mr. Edmondson, Assistant Astronomer of Armagh Observatory, for instructions as to the best practical methods of correcting my magnetic bearings, and for checking all the reductions of my barometric measurements; and lastly, (but very far from least,) to my friend Professor Haughton, Fellow of Trinity College, Dublin, for the series of formulae that have been the working tools of my research.
