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PAPERS.

"BY

Y obfervations fuch as this paper has been calculated to promote and facilitate, we are enabled to refolve a problem not only of great confequence, but in which we are all immediately concerned. Who, for inftance, would not with to know what degree of permanency we ought to afcribe to the luftre of our fun? Not only the ftability of our climates, but the very existence of the whole animal and vegetable creation itself is involved in the question. Where can we hope to receive information upon this fubject, but from aftronomical obfervations? If it be allowed to admit the fimilarity of ftars with our fun as a point eftablished, how neceffary will it be to take notice of the fate of our neighbouring funs, in order to guefs at that of our own! That ftar which among the multitude we have dignified by the name of fun, to-morrow may flowly begin to undergo a gradual decay of brightness, like Bleonis, a ceti, a draconis, durfæ majoris, and many other diminishing ftars that will be mentioned in

my catalogues. It may fuddenly increafe, like the wonderful ftar in the back of Caffiopea's chair, and the no lefs remarkable one in the foot of Serpentarius; or gradually come on like ẞ geminorum, ß ceti,

fagittarii, and many other increafing stars, for which I also refer to my catalogues. And lastly, it may turn into a periodical one of 25 days duration, as algol is one of three days, cephei of 5, 8 lyra of 6, antinoi of 7 days, and as many others, are of various periods.

"Now, if by a proper attention to this fubject, and by frequently comparing the real ftate of the heavens with fuch catalogues of brightnefs as mine, it fhould be found that all, or many of the ftars which we now have reafon to fufpect to be changeable, are indeed fubject to an alteration in their luftre, it will much leffen the confidence we have hitherto placed upon the permanency of the equal emiffion of light of our fun. Many phænomena in natural history feem to point out fome paft changes in our climates. Perhaps the easiest

way

way of accounting for them may be to furmife that our fun has been formerly fometimes more and fometimes lefs bright than it is at prefent. At all events, it will be highly prefumptuous to lay any great ftrefs upon the stability of the prefent order of things; and many hitherto unaccountable varieties that happen in our feafons, fuch as a general severity or mildnefs of uncommon winters or burning fummers, may poffibly meet with an eafy folution in the real inequality of the fun's

rays.

"A method of afcertaining the quantity or intenfenefs of folar light might be contrived by fome photometer or inftrument properly conftructed, which ought probably to be placed upon fome high and infulated mountain, where the influence of various causes that affect heat and cold, though not entirely

removed, would be confiderably leffened. Perhaps the thermometer alone might be fufficient. For though the luftre of the fun fhould be the chief object of this research, yet, as the effect of light in producing expanfion in mercury feems to be intimately connected with the quantity of the incident folar rays, it may be admitted that all conclufons drawn from their action upon the thermometer will apply to the investigation of the brilliancy of the fun. And here the forms laid down by Mr. Mayer, in his little treatise De Variationibus Thermometri accuratius definiendis, may be of confiderable fervice to distinguish the regular caufes of the change of the thermometer from the adventitious ones, among which I place the probable inftability of the fun's luftre."

HE extraordinary circum

“THE ftance of native gold being

found in this vicinity, early excited my attention, and led me to feize the first opportunity that prefented itfelf, after my late arrival here, to infpect the place where the difcovery was made.

"I went thither on Tuesday, the 3d of this month, with Mr. Lloyd, of Havodynos, and Mr. Weaver. The former having given you fome account of the circumstances which attended the original difcovery, and, fince he left me, a favourable day having enabled me to take a fecond view of the adjacent coun

try, I fhall now attempt to defcribe the general appearance, and add fuch further information as has come to my knowledge.

"The workings which the peafantry recently undertook are on the north-eaft fide of the mountain Croughan Kinfhelly, within. the barony of Arklow, and county of Wicklow, on the lands of the earl of Carysfort, wherein the earl of Ormond claims a right to the minerals, in confequence (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 Ire

land; which grant was renewed and confirmed by queen Elizabeth, and again by king Charles the Second. "The fummit of the mountain is the boundary between the counties of Wicklow and Wexford; seven English miles weft from Arklow, ten to the fouth-westward of Rathdrum, and fix fouth-wefterly from Cronebane mines; by eftimation about fix hundred yards above the level of the fea. It extends W. by N. and E. by S. and ftretches away to the north-eastward, to Ballycoage, where fhafts have formerly been funk, and fome copper and magnetic iron ore has heen found; and thence to the N. E. there extends a tract of mineral country, eight miles in length, running through the lands of Ballymurtagh, Ballygahan, Tigrony, Cronebane, Connery, and Kilmacoe, in all which veins of copper ore are found; and terminating at the flate quarry at Balnabarny.

"On the highest part of the mountain are bare rocks, being a variety of argillite, whofe joints range N.N.E. and S.S.W. hade to the S.S.W. and in one part include a rib of quartz, three inches wide, which follows the direction of the trata. Around the rocks, for fome diftance, is found ground, covered with heath; defcending to the eaft ward, there is fpringy ground, abounding with coarfe grais; and below that, a very extenfive bog, in which the turf is from four to nine feet thick, and beneath it, in the fubftratum of clay, are many angular fragments of quartz, containing chlorite, and ferruginous earth. Below the turbary the ground falls with a quick defcent, and three ravines are obferved. The central one, which is the most confiderable, has been worn by torrents, which derive their fource from the

bog; the others are formed lower down the mountain by fprings, which uniting with the former, below their junction the gold has been found. The fmaller have not water fufficient to wash away the incumbent clay, fo as to lay bare the fubftratum; and their beds only contain gravel, confifting of quartz with chlorite, and other substances of which the mountain consists. The great ravine presents a more interefting afpect; the water in its defcent has, in a very short distance from the bog, entirely carried off the clay, and confiderably worn down the fubftrata of rock, which it has laid open to inspection.

"Defcending along the bed of the great ravine, whofe general courfe is to the eastward, a yellow argillaceous fhiftus is firút feen; the lamina are much shattered, are very thin, have a light hade to the S.S.W. and range E.S.E. and W.N.W. Included within the shift, is a vein of compact barren quartz, about three feet wide, ranging N.E. and S.W.; below this is another vein, about nine inches wide, having the fame range as the former, and hading to the northward, confifting of quartz, including ferruginous earth. Lower down, is a vein of a compact aggregate fubftance, apparently compounded of quartz, ochraceous earth, chert, minute particles of mica, and fome little argillite, of unknown breadth, ranging E. and W. hading faft to the fouthward, and including ftrings of quartz, from one to two inches thick, the quartz containing ferruginous earth. The yellow argillaceous fhiftus is again feen with its former hade and range; and then, adjacent to a quartz vein, is laminated blue argillaceous fhiftus, ranging N.E. and S.W and hading S. E.; which is after

wards

wards feen varying its range and hade, running E.N.E. and W.S.W. and hading N.N.W.; lower down, the blue fhiit is obferved more compact, though ftill laminated. The ground, lefs fteep, becomes fpringy, is inclosed, and the ravine, hallower, has depofited a confider able quantity of clay, fand, and gravel. Following the courfe of the ravine, or, as it may now more properly be called, the brook, arrive at the road which leads to Arklow; here is a ford, and the brook has the Irish name of Aughatinavought (the river that drowned the old mán); hence it defcends to the Aughrim river, just above its conAuence with that from Rathdrum, which, after their junction, take the general name of the Oo, that, difcharging itself into the fea near the town of Arklow, forms an har bour for vessels of fmall burthen.

"The lands of Ballinvally are to the fouthward, and the lands of Ballinagore to the northward, of the ford, where the blue thiftus rock, whofe joints are nearly vertical, is feen ranging E.N.E. and W.S.W. including fmall ftrings of quartz, which contain ferruginous earth. The fame kind of earth is alfo feen in the quartz, contained in a vein from ten to twelve inches wide, ranging E.N.E. and W.S.W. and hading to the fouthward, which has been laid open in forming the Arklow road.

"Here the valley is from twenty to thirty yards in width, and is covered with fubftances, washed down from the mountain, which on the fides have accumulated to the depth of about twelve feet, A thin ftratum of vegetable foil lies uppermoft; then clay, mingled with fine fand, compofed of fmall particles of quartz, mica, and shift; beneath which the fame Subftances

are larger, and conftitute a bed of gravel, that alfo contains nodules of fine grained iron ftone, which produces 50 per cent. of crude iron: incumbent on the rock, are large tumblers of quartz, a variety of argillite and fhiftus; many pieces of the quartz are perfectly pure, others are attached to the fhiftus, others contain chlorite, pyrites, mica, and ferruginous earth; and the arfenical cubical pyrites fre quently occurs, imbedded in the blue fhiftus. In this mafs of mat ter, before the workings began, the brook had formed its channel down to the furface of the rock, and between fix and feven feet wide, but in times of floods extended itself entirely over the valley.

"Refearches have been made for the gold, amidft the fand and gravel along the run of the brook, for near half a mile in length; but it is only about one hundred and fifty yards above, and about two hun dred yards below the ford, that the trials have been attended with much fuccefs: within that space, the valley is tolerably level, and the banks of the brook have not more than five feet of fand and gravel above the rock; added to this, it takes a fmall turn to the fouthward, and, confequently, the rude furfaces of the fhiftus rock in fome degree crofs its courfe, and form natural impediments to the particles of gold being carried further down the ftream, which still lower has a more rapid defcent; befides, the rude manner in which the country people worked, feldom enabled them to penetrate to the rock, in those places, where the fand and gravel were of any material depth. Their method was, to turn the course of the water wherever they deemed neceffary, and then, with any inftruments they could procure, to

dig holes down to the rock, and by washing, in bowls and fieves, the fand and gravel they threw out, to feparate the particles of gold which it contained; and from the flovenly and hafty way in which their operations were performed, much gold moft probably efcaped their fearch; and that indeed actually appears to have been the cafe; for fince the late rains wafhed the clay and gravel which had been thrown up, gold has been found lying on the furface. The fituation of the place, and the conftant command of water, do, however, very clearly point out the great facility with which the gold might be feparated from the trash, by adopting the mode of working practifed at the be managed tin ftream works in the county of Cornwall; that is, entirely to remove (by machinery) the whole cover off the rock, and then wash it in proper buddles and fieves. And by thus continuing the operations, conftantly advancing in the ravine towards the mountain, as long as gold fhould be found, the vein that forms its matrix might probably be laid bare.

"The discovery was made public, and the workings began, early in the month of September laft, and continued till the 15th of October, when a party of the Kildare militia arrived, and took poffemon by order of government; and the great concourfe of people, who were bufily engaged in endeavouring to procure a fhare of the treafure, immediately defifted from their labour, and peaceably retired, "Calculations have been made, that during the foregoing period, gold to the amount of three thoufand pounds Irish fterling was fold to various perfons; the average price was three pounds fifteen fhillings per ounce; hence eight hun

dred ounces appear to have been collected within the fhort space of fix weeks.

"The gold is of a bright yellow colour, perfectly malleable; the fpecific gravity of an apparently clean piece 19,000. A fpecimen, affayed here by Mr. Weaver, in the moift way, produced from 24 grains, 2248 grains of pure gold, and 14 of filver. Some of the gold is intimately blended with, and adherent to quartz; fome (it is faid) was found united to the fine grained iron stone, but the major part was entirely free from the matrix; every piece more or lefs rounded on the edges, of various weights, forms, and fizes, from the most minute particle up to 2 oz. 17 dwts,; only two pieces are known to have been found of fu perior weight, and one of those is 5, and the other 22 ounces.

"I much regret not having been prefent when the work was going on, that I might have seen the gold as found, before prepared for fale by breaking off any extraneous matter that adhered; for in that state, a proper attention to the subftances with which it was united, and a fubfequent diligent infpection of the feveral veins that range through the mountain, might affift towards the difcovery of that from whence it was detached.

"I fhall fhortly return to England; and on my arrival, will fend fpecimens of the gold, and of the different fubftances of the moun. tain, to be depofited (if you think proper) in the collection of the Royal Society,

"And am, with great respect, &c.

"ABRAHAM MILLS. "The bearings are all taken by the compafs, without allowing for the variation.

*Befides