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Mar., 1875. BYE-GONES. 193 THE PHOSPHORITE DEPOSITS OF NORTH WALES. At a meeting of the Geological Society of London on Feb. 10, a Paper on this subject by Mr D. C. Davies, F.G.S., of Oswestry,was read; and one of the complete analyses of the phosphate which accompanied it was made by Mr D. Hesketh Richards of Maesbury. We take the following from the official Abstract of the proceedings :— The deposit of phosphate of lime described by the author is a bed varying from 10 to 15 inches in thickness, which occurs at the top of the Bala limestone over a considerable district in North Wales, having been detected in various localities from Llanfyllin to the hills north and west of Dinas Mawddwy. The bed is rendered black by the presence of graphite, and appears to consist of concretions of various sizes cemented together by a black matrix. The concretions are richest in phosphate of lime, some of them containing 64 per cent ; the average amount of the bed, including the matrix, is 46 per cent. The deposit is underlain by a bed of crystalline limestone, and sometimes divided by thin beds of similar limestone into two or three layers. The author noticed the principal fossils occurring in the Bala limestone below the phosphorite beds, and stated that many of those in the overlying shales, up to a certain distance above the bed, are phosphatized. The author referred to the presence of phosphate of lime in the inner layers of Unio and Anodonta to the amount of as much as 15 per cent., and thought that the phosphate of lime in the deposit was probably of organic origin. It may have been an ola sea-bottom on which the phosphate of lime of Mollusca and Crustacea was accumulated dHring a long period, and seaweeds may also have contributed their share. It probably represented the remains of an ancient Laminarian zone. The author suggested that the phosphatic nodules of the so-called coprolite beds in other parts of England might have been derived from the denudation of similar deposits. Discussion. Prof. Seeley remarked that the concretionary character and dense structure of the nodules, as well as their coating of gra¬ phite indicative of vegetable origin, were possessed by them in common with the nodules in the Cambridge Upper Greensand. He thought that Mr Davies had laid too much stress on the animal origin of the phosphate, for the deposits richest in fossils do not contain more than 8 per cent, of phosphate of lime; and if its origin was as supposed, we should expect phosphatic beds to be much more numerous than they are in nature. The recent researches in the ' Challenger ' have revealed facts which seem to have some bearing on this question. The shells of Fcramini- fera in falling through the water have their shells dissolved to some extent. Prof. Rogers had shown that while the process of solution was going on the carbonate of lime was being rede- posited in other shells which had not yet fallen, and that in falling some of them may become filled with phosphate of lime. This process might lead to the deposition of a gelatinous mass on the sea-bottom, which might ultimately be converted into the nodules. He said that he had ascertained that most marine plants contain a considerable percentage of phosphate of lime, and he was therefore more inclined to accept the view that the phosphate in these deposits was due to vegetable organisms than to assign them an animal origin. Still he thought there must have been some unusual circumstances to lead to the formation of such deposits, and he had therefore argued in favour of there Peu?g a» excess of phosphoric acid in the sea at that time, due «> the denudation of apatite or other phospnatic matter of vol¬ canic origin. Mr Chableswoeth did not agree with Prof. Henslow's views as to the coprolitic nature of the phosphatic nodules, and was pre¬ pared to accept the notion of their beinot redeposited from dis¬ solved apatite. The discovery of phosphatic beds in such early wXu ?? ,nose of the Bala series seemed to him to be of the HtT interest. fWii?AWKINS Johnson observed that Dr Pereira had shown »«h J, was aboat 7 Per ceat- of Pbosphate of lime in the menon sea"weed> whicn mi6ht 8uffice to produce the pheno- irr^i^A*ERItuGT0N W' Smith attributed the thin coating of thickn«L <• "jV^sence of graphitic schists of considerable nodnut atthat horizon. It was constantly the case that hard under^'n^ch as lron8tones, presented the appearance of having poliffi l*0?® raMiing process which gave their surface a CS W£d aPPe«ance. He therefore thought that wayaf?h«»lnldbeen ag^gated together much in the same way as the well-known nodules in Carboniferous beds. Mr D. Forbes was inclined to believe with Mr Seeley that the eruptive rocks were a source of the phosphoric acid, as his ex¬ perience had shown him that all these rocks contain apatite in greater or less amount. Analyses which he had made of lime¬ stones, almost wholly composed of shells and containing Crus¬ tacea, showed so small an amount of phosphoric acid that he thouaht the amount of phosphorus contained in these organisms had generally been overrated. He asked the Fellows present where he could find reliable analyses of the shells of Mollusca and Crustacea, as he had met with very few. Mr Gwyn Jepfbets remarked that though the freshwater Unio and Anodonta might have so much phosphate of lime in their composition, marine shells, such as oysters, contained only about 1£ per cent., and these beds after all were not of freshwater but of marine origin. The shells of Crustacea might perhaps contain more. Curious Appearance op Lights.—Mr G. T. Picton- Jones, Yoke House, Pwllheli, writes to The Field as follows: "Some few days ago we witnessed here what we have never seen before—certain lights, eight in number, ex¬ tending over, I should-say, a distance of 8 miles; all seemed to keep their own ground, although moving in horizontal, perpendicular, and zig-zag directions. Sometimes they were of a light blue colour, then like the bright light of a carriage lamp, then almost like an electric fight, and going out altogether, in a few minutes would appear again dimly, and come up as before. One of my keepers, who is nearly 70 years of age, has not, nor has any one else in this vicinity, seen the same before. Can any of your numerous readers inform me whether they are will-o'-the-wisps, or what? We have seen three at a time afterwards on four or five occasions." March 3, 1875. NOTES. SAINT DAVID'S DAY (Feb. 28, 1872, Mar. 5, 1873).—On St. David's Day an immense silver-gilt bowl, containing ten gallons, which was presented to Jesus College, Oxford, by Sir Watkin Williams Wynn, in 1712, is filled with Swig, and handed round to those who are invited to sit at the festive and hospitable board. (See Hone's Year Book, p. 265, referring to "Oxford Night Caps"). On March 1, 1738, I first saw a Welchman with a leek in his hat, and thought it would have been better in his porridge. (Diary of Wm. Hutton, F.S.A., of Bir¬ mingham). "Tuesday, March 1st, being St. David's Day, the same was observed at Court as a high festival. The Rt. Rev. the Ld. Bp. of Llandaff preached an excellent sermon at St. Andrew's, Holbourn, where the collection and at Merchant Taylors-hall amounted to £111 9s. 5d., exclusive of what is apprehended may be given by the Welch gentle¬ men whe met at the Devil Tavern, which money is appropriated to the Welch Charity School on Clerkenwell- green; where at present 40 poor boys, sons of Welch parents, benefited by no parochial charity, are cloathed & educated, and put out to proper trades, or the sea."— Gents: Mag: 1757. QUERIES. ANCIENT KNIGHTS OF CAMBRIA.—The Lon¬ don papers of June 1821 stated that when His Majesty visited Wales a new order of Knighthood was to be created: Title, Order of the Ancient Knights of Cambria; Ribbon, Leek Green with white edges; in the centre of the star the Welsh Harp. Dr Burgess, Bishop of St Davids, was mentioned as the probable prelate of the order, and Sir Watkin was named as the most likely to be first creation. 49