copper, of which several run nearly in a parallel direction from east to west.
The peculiarity here is, that there are several cross courses which run north and south, the greatest part of which contain no metal : these meeting with the lodes of copper ore, interrupt their continuity, or, as is expressed by the miners, heave them out of their direction, so that at the place of intersection the copper lodes seem to have been forced aside eighteen or twenty inches. One of these cross courses has of late been discovered to yield silver in no inconsider- able quantity; but with this particular circumstance, that at and near the place of intersection the ores both of silver and copper are much less productive than at some distance from it. The silver ore con- sists of a mixture of galena, native bismuth, gray cobalt, vitreous silver, and native silver chiefly in a capillary form.
found imbedded. By Mr. Charles Combe, of Eseter College, Oaford. In a Letter to the Right Hon. Sir Joseph Banks, Bart. K.B.
P.R.S. Read February 19, 1801. [Phil. Trans. 1801, p. 165.]This tusk, which weighed fifty pounds, and measured about six feet in length, is supposed to have been imported from Africa, and was purchased at Liverpool by a manufacturer of Birmingham. COn shaking it, a rattling noise was heard near the middle part, which, on cutting tbe tooth transversely, was found to be occasioned by an iron spear-head, about six inches and a half long, which lay in the longitudinal direction of the tooth, with the point foremost, and was considerably corroded. It is conjectured that the spear had entered at the basis of the trunk, between the interior angle of the eye and the proboscis, the cavity of the tusk being placed immediately be- neath this part. From the quantity of bony matter that had been formed round this extraneous body, it is inferred that the animal must have lived a considerable time after it had received the wound. The spear-head and the part of the tooth in which it had been im- bedded were exhihited to the Society at the close of the Meeting.
of Cornwall. By the Count de Bournon Communicated by the Right Hon. Sir Joseph Banks, Bart. K.B.P.R.S. ReadFebruary 19,
1801. [Phil. Trans. 1801, p. 169.]In the mine called Huel Gorland, in the parish of Gwennap in Cornwall, has lately been discovered a species of ore, consisting of different combinations of the arsenic acid with copper and iron, which, though some mention have been made of it by German writers as having been found in Silesia, appears yet, from the great abundance afforded by the above-mentioned mine, to be almost peculiar to this country. After an historical account of the little that has hitherto been known concerning this substance, Count Bournon
