Events of the deepest excitement supersede one another so rapidly, that it can scarcely be expected the public will be solicitous to know why so long a period has been allowed to pass since the return of the Niger Expedition, before any authentic statement of its proceedings has been given to the world.
The authors, conceiving that a faithful record of the progress of that philanthropic experiment is due to the public, as well as in justice to the conductors of it, have ventured to draw up the following Narrative. They are indebted to the late Dr. Vogel, Mr. Roscher, and Dr. Stanger, of whose botanical and geological journals (placed at their disposal by the kindness of Captain Trotter) they have availed themselves; and they have to express their deep obligations to Dr. McWilliam for the account of the proceedings of H. M. Steam-vessel 'Albert' whenever separated from the 'Wilberforce,' and for a series of well-arranged tables of the vital statistics.
The account of the second ascent of the 'Wilberforce,' is derived from the report of Lieutenant Webb to the Admiralty.
Some valuable philological remarks on the vocabularies of the African tribes have been kindly furnished by Dr. Latham.
Colonel Sabine, R.A., had obligingly undertaken to reduce the magnetical observations, but the attention required by the numerous scientific works to which he is so unremittingly devoted, has prevented their timely preparation; grateful acknowledgments are, however, due to that officer for supplying the accompanying letter, which will show that this important branch of science was not neglected.
"I regret extremely, that the reduction and co-ordination of your magnetic observations are not sufficiently advanced to enable me to furnish you with such an abstract of the results, and such a general notice of their importance and bearing on our knowledge of the magnetism of the earth, as would have had a proper place in your Work, and have been satisfactory to yourself and to your readers. Your determinations of the absolute values of the magnetic declination, dip, and intensity of the magnetic force on the western coast of Africa, will undoubtedly supply for the magnetic maps now in construction, the principal part of the materials for that quarter of the globe.
"Having make some progress in reducing these, I have had frequent occasion to admire the scrupulous and persevering attention which you paid to all those minute circumstances on which, in observations of this nature, the accuracy of the results is mainly dependent; and which is the more important in your case, because the interior of the continent of Africa is altogether without such determinations, and the direction of the magnetic lines is consequently more than usually dependent for its correctness on the accuracy of the observations on the coasts. I need scarcely say, that the peculiar objects and circumstances of your Expedition, and the sufferings which it underwent, render such careful attention to minutiae the more worthy of admiration. The co-ordination of your observations on Term-days, with the simultaneous observations made in different parts of the globe, is also in progress, and promises to afford some interesting and valuable results, particularly the Term-day of April, 1842, which you observed at Fernando Po. It was a day of considerable magnetic disturbance apparently over the whole globe, and Western Africa seems to have had its full share. Fernando Po, as a station, is well placed, in connection with the surrounding stations of the Cape of Good Hope, St. Helena, Algiers, and Southern Europe.
"My dear Sir,
"Very sincerely yours,
To Captain William Allen, R.N. F.R.S.
The prominence given in the following Narrative to the 'Wilberforce,' arises from the fact of that vessel having been actively engaged during the whole period of the Expedition, the command of which devolved on Captain William Allen.
June 20, 1848.