Page:Proceedings of the Royal Society of London Vol 4.djvu/494

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more or less globular, composing what have been termed fibrinous corpuscles. These corpuscles have been considered to be the nuclei of cells ; but the author regards them as being merely accidental fragments of broken down tissues, adhering to the filaments, and noways concerned in their developement. The more regularly dis- posed granules, which are observed to occupy the spaces intervening between the filaments composing the ordinary cellular tissue, he considers as being fatty matter deposited within these spaces. He, in like manner, regards the observations tending to show the celltdar origin of the fibrous, cartilaginous, and osseous tissues, as altogether fallacious ; and maintains that the cells, which these animal textures exhibit when viewed under the microscope, are simply spaces occur- ring in the more solid substance of these structures, like the cavities which exist in bread. These views are pursued by the author in discussing the formation of the skin, the blood-vessels, and the nerves, and in controverting the theory of secretion, founded on the action of the interior surfaces of the membranes constituting cells.

2. " Contributions to Terrestrial Magnetism." — No. V. By Lieut.- Colonel Edward Sabine, R.A., F.R.S.

In this paper the author details and discusses the magnetic obser- vations made on board Her Majesty's ships Erebus and Terror, between October 1840 and April 1841, being the first summer which the expedition under the command of Captain James Clark Ross, R.N., passed within the Antarctic Circle.

The elimination of the influence of the ship's iron in the calcula- tion of the results of these observations occupies a considerable por- tion of the paper. Formulae for this purpose are derived from M. Poisson's fundamental equations, and the constants in the formulae are computed for each of the two ships, from observations made on board expressly with that object. With these constants, tables of double entry are formed for each of the three magnetic elements, namely, declination, inclination, and intensity, giving the required corrections of each, for all the localities of the voyage.

These and other corrections being applied, the results are tabu- lated and charts formed from them. The full consideration of the charts is postponed until the whole of the materials collected by the Antarctic Expedition shall be before the Royal Society. Meanwhile the paper concludes with the following general remarks, viz.

1. The observations of declination, particularly those which point out the course of the lines of and of 10° east, indicate a more westerly position than the one assigned by M. Gauss in the ^ Atlas des Erdmagnetismus,' for the spot in which all the lines of declina- tion unite. The progression of the lines in the southern hemisphere generally, from secular change, is from east to west ; the difference consequently is in the direction in which a change should be found in comparing earlier with more recent determinations.

2. The general form of the curves of higher inclination in the southern hemisphere is much more analogous to that in the northern than appears in M. Gauss's maps. For example, the isoclinal line