Page:Proceedings of the Royal Society of London Vol 1.djvu/132

Rh years of age. In these cases the excrescence was a tumour no larger than a pea, but the appearance of which threatened the formation of a cancer. Both these were successfully removed by the ligatures above described; and, except a small ﬁssure, no kind of deformity was left upon _the tongue.

The principal inference derived from these operations is, that the internal structure of the tongue is less irritable than almost any other organized part of the body; and that therefore the peculiar substance which is interposed between the fasciculi of its muscular ﬁbres is not in any respect connected with the nerves which pass through its substance to the organ of taste, but is merely a soft medium, which is intended to facilitate the action of the organ in its different parts. It also appears from these observations, that the nerves of the tongue may be more easily compressed and deprived of their power of com- municating sensation than nerves in general; and that an injury in- ﬂicted on them is not productive of any diseased action in the trunk of the injured nerve.

Lastly, the advantages to be derived in the practice of surgery from the success of these operations, are brieﬂy stated; and indeed the removing with safety the whole part of a tongue which may have taken on a disposition to be cancerous, Will easily be allowed to be a most material improvement in that important branch of the medical profession.

Concerning the transit of Mercury, as the times at which the observations were made were not the chief object of the investigation, the detail here given is only to be considered as denoting the order of their succession. When the planet was ﬁrst seen on the disc of the sun on the 9th of November last at about 40' after seven in the morning, it was easily distinguished from the Openings in the luminous clouds generally called spots, its perfect roundness being sufﬁcient to point it out, had its place not been previously known. As the morning advanced, its termination became by degrees still more accurately deﬁned; and the corrugations of the luminous surface of the sun were visible up to the very edge of the planet. Near the egress, when the sun and planet were nearly in the meridian, particular attention was paid to the appearance that was thought to indicate an atmosphere round Mercury; but nothing of the kind could be perceived, its periphery remaining sharp and well deﬁned to the very last. It was also observed that the appearance of the planet, during the whole transit, never deviated in the least from the spherical form; whence it is inferred, that unless its polar axis should have happened to be situated in a line drawn from the eye to the sun, the planet cannot be materially ﬂattened at its poles.