one of these is through those lacteals, which pours the absorbed chyle into bags, in which it receives an addi. tion of animal fluids. The other pas sage of the chyle is through those lacteals which form a plexus on the inside of the bags; through these vessels it passes with some difficulty, on account of their communications with each other; and it is conveyed by them to the thoracic duct, in the same state that it was when first imbibed from the intestines. The lacteals, which pour the chyle into the bags, are similar to those which terminate in the cells of the mesenteric glands of other animals: there is also an analogy between the distribution of the lacteals on the inside of these bags, and that which we sometimes observe on the outside of the lymphatic glands in general. In either case, a certain number of the va inferentia, as they are termed, com. municate with one another, and with other vessels, named vase efferentia.

vasa

By this communication, the progress of the fluids contained in these vessels is in some degree checked; which impediment in. creases the effusion into the cavities of the gland made by the other lacteals: but should these cavities be obstructed, from disease, or other causes, an increased determination of fluids into the communicating absorbents must happen, which would overcome the resistance produced by their mutual inoscultations, and the contents of the vessels would be driven forwards towards the trunk of the system. In the whale, as in other animals, we And that the impediment, occasioned by this communication of lacteals, is greatest in the first glands

at which they arrive after having left the intestines.

The ready termination of so many arteries in the mesenteric glands of the whale, makes it ap. pear probable that there is a copi. ous secretion of the fluids mixed with the absorbed chyle; and, as I have before observed, a slimy blood-coloured fluid was found in them. As the orifices of veins were open, it appears probable that the contents of the bags might pass in some degree into those vessels.

The eminent anatomists, Albinus, Meckel, Hewson, and Wrisberg, were of opinion, that the lym phatic glands were not cellular, but were composed of convoluted absorbing vessels. This notion seems, however, to have been gradually declining.

Mr. Cruikshank has of late publicly maintained a contrary opinion; and has shewn, that the cells of these glands have transverse communications with each other; which it is not likely they would have, if they were only the sections of convoluted vessels. Some addi. tional observations have occurred to me confirming this opinion, and which, as I believe they have not been publicly noticed by others, I beg leave to relate to this society. I have injected the lymphatic glands of the groin and axilla of horses with wax, and afterwards destroyed the animal substance by immersing them in muriatic acid. In some of these glands the wax appeared in very small por. tions, and irregularly conjoined; which is a convincing proof, that it had acquired this irregular form from having been impelled into numerous minute cells. But in se

veral instances, I found one solid lump of wax, after the destruction of the animal substance: and it appears to me sufficiently clear, that the glands which were filled in this manner, were formed internally of one cavity, and were not, as is commonly the case, composed of many minute cells. I have also filled the glands of this structure, in the mesentery of an horse, with quicksilver: I have then dried them, cut open the bags, and introduced a bristle into them through the vas inferens. And in the human mesentery, after having injected the artery, I have filled a bag resembling a gland with quicksilver; which being opened, a mixture of injection and quicksilver was found in its cavity.

That the lymphatic glands in most animals are cellular, may not, perhaps, be hereafter doubted: that they are sometimes mere bags, analogy and actual observation induce me to believe. It might be said, that in those instances which I have related, the cells were burst, or that the glands were diseased : to which I can only reply, that there was no appearance to lead me to - such a conclusion.

If, then, the lymphatic glands are either cellular, or receptacles resembling bags for the absorbed fluids, we are naturally led to inquire, what advantages arise from this temporary effusion of the contents of the absorbents. That there is a considerable quantity of fluids poured forth from the arteries of the whale; to mix with the absorbed chyle is very evident; nor can it be doubted that the same thing happens in other animals; for the cells of the lymphatic glands are easily inflated, and injected from the arteries,

The ready communication of these bags with the veins of the whale, induced me to examine whether I should ascertain any thing similar in other animals. Air impelicd by the lymphatic glands, however, seldom gets into veins : sometimes indeed veins are injected from these glands; but when this has occurred to me, I have observed an absorbent arising from the gland, and terminating in the adjacent vein.

These remarks, perhaps, may not be very important; such, however is the nature of the subject, that all the knowledge we have hitherto obtained of the absorbing vessels has been acquired by fragments, and all car future acquisitions must be made in the same man. ner: I have wished, therefore, by offering these observations, to contribute my mite to the gene. ral stock of our knowledge of this subject.

An Account of the late Discovery of Native Gold in Ireland. In a Letter from John Lloyd, Esq. to. Sir Joseph Banks, Bart. From

the same.

Cronbane Lodge, near Rathdrum, the 4th November, 1795.

DEAR SIR,

THE late very important mine.. ralogical discovery in Ireland, and a desire I had long entertained of visiting the celebrated copper mine at this place, together with the opportunity that presented it self, of making my tour in com. pany with our friend Mr.Mills, i who is one of the proprietors, 23 welds sole director of the mine, determined me to seize this mo..

ment

ment for my excursion; and yes. serday Mr. Mills and I visited the spot, where so much pure gold has been of late taken up, being distant about five miles from this place.

About seven miles westward of Arklow, in the county of Wicklow, there is a very high hill, perhaps 6 or 700 yards above the sca, called Croughan Kinshelly, one of whose NE abutments, or batgresses, is called Ballinnagore, to which the ascent may be made in half or three quarters of an hour. Should you have Jacob Nevil's map of the county of Wicklow, published in 1760, at hand, by casting your eye on the river Ovo, which runs by Arklow, at about four miles above the latter place, you will perceive the conflux of two considerable streams, and of a third about half a mile higher up, close to a bridge. By tracing this last to its source, you will come to a place, set down in the map Ballinvalley: this is a ravine between two others, that run down the side of the hill into a semicircular, or more properly, semi-elliptical valley, which extends in breadth from one summit to the other of the boundary of the valley, and across the valley three quarters of a mile, or somewhat less. The hollow side of the hill forms the termina. tion of the valley, and down which fun the three ravines abovemen. tioned. At their junction, the brook assumes the name of Ballinasloge; at this place the descent is not very rapid, and so continues a hanging level for about a quarter of a mile, or somewhat more, when the valley grows narrower, and the sides of the brock become steeper; and it should seem that, some rocky bars across the course

of the brook have formed the gravelly beds, above, over, and through which the stream flows, and in which the gold is found. The bed of the brook, and the adjacent banks of gravel on each side, for near a quarter of a mile in length, and for 20 or 30 yards in breadth, have been entirely stirred and washed by the peasants of the country, who amounted to many hundreds, at work at a time, whilst they were permitted to search for the metal.

A gentleman, who saw them at work, told me, he counted above 300 women, at one time, besides great numbers of men and children.

The stream runs down to the NE from the hill, which seems to consist of a mass of schistus and quartz; for on examination of the principal ravine, which is now washed clean by the late heavy rains, the bottom consisted of schistus, intersected at different distances and in various places, by veins of quartz, and of which substances the gravelly beds at the bottom, where the gold is found, seem to consist.

Large tumblers of quartz are thickly scattered over the surface of the top of the hill, under a turbary of considerable thickness, upon the removal of which these tumblers appear.

I shall not take up your time in attempting to give a minute geolo. gical description of this part of the country, as I have prevailed with Mr. Mills (who from his minute examinations, and practical know. ledge, is so conversant with the mineralogy of the county), to undertake that task, which I am persuaded he will perform to your satisfaction.

The gold has been found in

masses

cond view of the adjacent country, I shall now attempt to describe the general appearance, and add such further information as has come to my knowledge..

The workings which the pea santry recently underrock, are on the north east side of the mountain Croughan Kinshe.ly, within the barony of Arklow, and coun y of Wicklow, on the lands of the earl of Carysfort, wherein the Earl of Ormond claims a right to the minerals, in consequence (as I have been informed), of a grant in the reign of king Henry the second, by prince John, during his command of his father's forces in Ireland; which grant was renewed and confirmed by queen Elizabeth, and again by king Charles the second.

The summit of the mountain is the boundary between the counties of Wicklow and Wexford; seven English miles west of Arklow, ten to the south-westward of Rath drum, and six south-westerly from Crenchane mines, by estimation about six hundred yards above the level of the sea. It extends W by N and E by S, and stretches away to the north-eastward, to Bally coage, where shafts have formerly been surk, and some copper and magnetic iron ore has been found; and thence to the NE there extends a tract of mineral country, eight miles in length, running through the lands of Ballymurtagh, Bally. gahan, Tigrony, Cronebane, Con. nery, and Kilmacoe, in all which veins of copper ore are found, and terminating at the slate quarry at Balabarny.

On the bophony tain are ba

of argi ie, wide

NNE and SOW, nang to, the and an one part polpe a rib of quartz, three thes wide, which follows the direction at the strata. Around the rocks, for some distance, is found ground covered with heath; descending to the eastward, there is a springy ground, abounding with coarse grass; and below that,

a very extensive bog, in which, the turf is from four to nine feet thick, and be. neath it, in the substratum of clay, are many angular fragments of quartz, containing chlorite, and ferruginous earth. Below the turbary the ground falls with a quick descent, and three ravines are ob served. The central one, which is the most considerable, has been worn by torrents, which derive their source from the bog, the others are formed iower down the mountain by springs, which uniting with the former, below their junction the gold has been found. The smaller have not water sufficient to wash away the incumbent clay, so as to lay bare the substratum; and their beds only contain gravel, consisting of quartz with chlorite, and other substances of which the mountain consists. The great ravine presents a most interesting aspect; the water in its descent has, in a very short distance from the bog, entirely car. ried off the clay, and considerably worn down the substrata of rock, which it has laid open to inspection.

Descending along the bed of the great ravine, whose general course is to the eastward, a yellow argilla.

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