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HARDWICKE'8 SCIENCE-GOSS IP. 



18 ft. At the depth of 25 ft., an innumerable 

 quantity of hazel nuts, when they had become per- 

 fectly dry, were quite liard, the oak resembling bog 

 oak. A large quantity of bones, consisting of 

 shoulder-blades of the smaller animals, shin-bones, 

 and vertebrae, besides many others, both perfect and 

 in fragments, were brought to light. A bear's skull 

 was found amongst the rest. At a distance of 

 about half a mile, in almost a direct line with the 

 viaduct, while making a cutting through which the 

 line of rail was to pass, a number of small marine 

 shells, both fragmentary and entire, were found. 

 No doubt, had it been known that such objects 

 would have been discovered, greater care would 

 have been taken to collect them whole. As it was, 

 the greater part fell into the bands of the workmen, 

 and were either scattered or destroyed. —P. S. 



Glacial Drifts of North London.— Such 

 was the title of a paper read before the Geologists' 

 Association by Mr. Henry Walker, P.G.S., and 

 reprinted. It describes a recent exposure of the 

 glacial drift at Pinchley, and gives details of the 

 section, chiefly remarkable for the quantity of re- 

 deposited fossils from older formations, especially 

 chalk and lias, found there. The beds Mr. Walker 

 believes to be middle and upper glacial. The 

 drift beds lie, at Tiuchley Station, at a height of 

 390 feet above the ordnance datum-line. Mr. Walker 

 gives a very useful list of the places in the neigh- 

 bourhood where geologists may see the chalky 

 nature of the Middlesex boulder clay. 



Secondary Strata in Scotland.— A valuable 

 paper has recently been read before the Geological 

 Society, on the Secondary Rocks of Scotland, by 

 Mr. J. W. Judd, F.G.S. He states that these 

 rocks are represented only by a number of isolated 

 patches of strata situated in the Highlands and 

 Western Isles, which have been preserved from the 

 destructive effects of denudation either through 

 having been let down by great faults among the 

 Palaeozoic rocks, or through being sealed up under 

 vast masses of Tertiary lavas. The Cretaceous 

 rocks, yielding a beautiful series of fossils, were 

 discovered by Mr. Judd last summer on the main- 

 land, and in several of the islands of the West of 

 Scotland. The Oolitic rocks were shown to present 

 marked contrasts with the English series, in being 

 constituted, throughout their whole thickness, by 

 alternation of marine and estuarine series of beds, 

 in which respect they precisely resemble the 

 Oolitic rocks of Sweden. The rocks of Suther- 

 land, in which the Telerpefon was discovered, 

 are now proved to be of Triassic age, as Prof. 

 Huxley conjectured. 



The UrPER Cambrian Rocks.— Dr.- Hicks has 

 made another important communication to the 

 Geological Society of London, on the Tremadoc 



rocks in the neighbourhood of St. David's, South 

 Wales. Many of the fossils mentioned by him as 

 being recently discovered, are new species, and 

 some of them even new genera. Among the latter 

 is a Trilobite, named Neseuretus, among the former; 

 species of Theca, Bellerophon, Palasterina, Deiido- 

 crinus, &c., all of them highly organized forms. 

 Perhaps the most marked feature is the discovery 

 of species of Lamelllbranchiata in the Upper Cam- 

 brian rocks. Until now, they were restricted to 

 strata of later age. 



Polishing Stones, &c. — I Lave much pleasure 

 in giving " S. W.," who asks (in Science-Gossip> 

 Jan., p. 9) for information on this subject, the mode 

 I have for some years adopted with great success 

 for polishing agates, amber, coprolites, carnelians, 

 jet, malachite, marble, raother-o'-pearl, and many 

 other stones. First, to grind : — Get a piece of 

 thick sheet lead, about nine inches long by four 

 inches wide. Also a few ounces of emery of the 

 three last degrees of fineness, and using the coarser 

 kind first, rub down the agate, &c., with the aid of 

 a little water, on the lead. Having thus reduced 

 the agate to the size and shape required, the next 

 best thing, though not absolutely necessary, is to 

 rub the surface with a piece of snake-stone, keeping 

 it moistened the while with a little water. Small 

 and suitable pieces of snake-stone, with one side 

 beautifully smooth, can readily be obtained at any 

 marble or stone mason's for a few pence. Secondly, 

 to polish : — Get a piece of half-inch deal, about 

 eighteen inches long by six inches wide, and nail 

 tightly over it three thicknesses of cloth, the finer 

 the better for the upper piece. Strew some putty 

 powder over this ; wet it with water, then rub the 

 stone on it briskly till the polish is effected. After 

 this, if you want a very first-rate polish, for which 

 the extra trouble amply repays itself, make another 

 board similar to the first, using jeweller's rouge 

 instead of the putty powder ; but in all cases the 

 putty powder should be used first. — L. V. II. 



NOTES AND QUERIES. 



The Hydra. — In an article on the hydra in 

 the January number of Science-Gossip, the author 

 gives it as his opinion that the hydra does really 

 possess the power of paralyzing or stinging its 

 prey, and instances his having seen water-tleas that 

 had come in contact with its tentacles, but had 

 managed to disengage themselves, drop down life- 

 less. I remember Mr. Lewis, in one of his books, 

 states that he had watched those animals that had 

 apparently been stung l)y the hydrii, and found that 

 after Ijing at the bottom a short time, they swam 

 away apparently nothing tiie worse ; and also that 

 he found that when they were touched by a needle 

 they behaved in exactly the same manner. Is not 

 this a proof that they were merely shamming deatli ; 

 unless Mr. Fullagar believes that the needle 

 poss^esses the same paralyzing power as the hydra ? 

 I have myself, during several years, performed 



