HARDWICKE'S SCIENCE-GOSSIP. 



183 



Lambay, is a very dark and compact grey rock, very 

 fossiliferous in certain places. Corals are abundant, 

 projecting in relief, where weathered. Still farther 

 north on the coast, at Loughshinny, reached from the 

 Rush and Lusk station of the same railway, the 

 Lower Coal Measure shales appear with characteristic 

 fossils, Posidonoviya Becheri and Goniatites sphczricas, 

 the first-named shell defining the horizon of the junc- 

 tion beds between the Lower Coal Measure shales 

 and Upper Carboniferous Limestone. 



North of this, on the shore at Balbriggan, may be 

 seen black slates, with numerous Graptolites ; these 

 are principally single-celled species referred to G. 

 Hisingeri. At the Cardy rocks, a little more north, 

 fossils indicative of Caradoc age, are found in 

 brown shales, of which several species have been 

 enumerated. 



The great Irish Deer (Cervits megaceros) has been 

 found near Dublin, associated with the Reindeer 

 {Cervtts tarandus) ; it existed formerly in considerable 

 numbers in this neighbourhood, as in other parts of 

 Ireland. The Bog of Ballybetagh, near Kiltiernan, 

 on the boundaries of the counties of Dublin and 

 Wicklow, has supplied a great many examples of this 

 stupendous animal. Professor Oldham, in a paper 

 read before the Geological Society of Dublin, in 

 1847* records the discovery of the remains of at 

 least thirty individuals, accompanied by the head 

 and antlers, with other bones of a Reindeer (Cervits 

 tarandus), in the cutting for a drain in this bog. Dr. 

 A. Carte, in a paper read before the same society, f 

 gives an account of a skull and antlers of a Reindeer 

 from the Curragha Bog, near Ashbourne, county 

 Dublin (Sheet 101, Geol. Survey Maps). This 

 fine example, in the Royal Dublin Society's Museum 

 was found in a very similar deposit to that previously 

 mentioned, imbedded in marl and clay, under four or 

 five feet of peat. From the peculiar shape of the 

 brow antler, these specimens are proved to belong to 

 the Caribou, or "Barren ground" variety, which now 

 inhabits America between the sixty-third and sixty- 

 sixth degrees of north latitude, in the winter ; migra- 

 ting to the coasts of the Arctic Sea in summer. It is, 

 therefore, very interesting to meet with evidence of 

 the former existence of this variety of the Reindeer 

 in Ireland. 



Glacial action is evidenced by scorings of the rocks, 

 which are observable at Kilruddery, Bray, and at 

 Portraine ; by the transport of large masses, such as 

 that of granite, on the top of Bray Head, and the 

 distribution of boulders of various formations, in the 

 drift along the railway, near Killiney. 



The Eskers of Ireland are frequent over all the 

 low central plain ; they are continuous banks of drift, 

 composed of sand and gravel, sometimes fifteen or 

 twenty miles in length, with steep sides, varying from 



* your. Geol. Soc. of Dublin, vol. iii. p. 280(1848). 

 t Ibid., vol. x. p. 103 (1863-64). 



twenty feet to seventy feet above the general level. 

 One is to be seen three or four miles to the 

 west of Dublin, running from the banks of the 

 Dodder, past the old castle of Tymon, by the Green 

 Hills, to the valley of the Liffey. 



Should any member of the British Association 

 visiting Ireland wish to travel further, there are the 

 collieries near Castlecomer, county Kilkenny, and 

 Killenaule, county Tipperary, with anthracite coal and 

 numerous fossil plants, &c, in the shales, especially in 

 the collieries near Tipperary ; the celebrated old red 

 sandstone quarry at Kiltorcan, near Thomastown, 

 county Waterford, with its well-preserved plant 

 and fish remains; the promontory of Hook Head, 

 county Wexford, where the lower shales of the car- 

 boniferous limestone are covered with a profusion of 

 beautiful fossils, and at Sand Eel Bay, close adjoin- 

 ing, the junction between the Old Red Sandstone and 

 carboniferous strata may be seen ; the carboniferous 

 limestone between Limerick and Foynes, full of 

 good fossils ; the Upper Silurian rocks of the Dingle 

 promontory, county Kerry, more difficult of access, 

 but containing numerous fine fossils ; the cliffs of 

 Moher, county Clare, of Coal Measure strata, up- 

 wards of nine hundred feet high, looking out upon 

 the broad Atlantic, and the Llandovery strata of Con- 

 nemara ; the Silurian limestone of the Chair of Kil- 

 dare, with its profusion of fossils and intrusive 

 porphyry, like that of Lambay ; the hard chalk 

 "white limestone" of Antrim, capped by basalt, 

 with lias and Rhcetic beds, near Belfast and Larne ; 

 and the Miocene plant beds, associated with the iron 

 ores in the basalt, near Carrickfergus, and extending 

 over a considerable portion of the north of Ireland. 



MICROSCOPY, 



A Good Mounting Medium. — For some time I 

 was at a loss to find a good medium that would fix 

 a metallic or other ring to the glass slide, and at the 

 same time resist the action of thin balsam, that is, 

 balsam rendered thin by the addition of chloroform, 

 benzine, or turpentine. I tried gold size, and allowed 

 the slip to remain for some months to get perfectly 

 hard before attempting to use it. This was mode- 

 rately successful as far as the turpentine-balsam went, 

 but with the chloroform and benzine it was a com- 

 plete failure. Marine glue is, of course, entirely out 

 of the question, it being so rapidly and easily dis- 

 solved by the two last-named fluids. The only 

 medium I have found, that is thoroughly to be relied 

 upon, is a cement known as " Thompson's Cement," 

 which is made by Messrs. Thompson & Capper, of 

 4, Lord Street, Liverpool. I give the name and 

 address, as it is important to know where it can be 

 obtained. I have used it now for some time with 

 the most satisfactory results. The balsam, no matter 



