54 



SCIENCE-GOSSIP. 



Geological Sections. — A student writes to ask 

 if any of our readers, versed in practical geology, 

 will tell him of any published work which would 

 show a student how to construct sections from 

 geological maps ? Books tell him how to construct 

 them from actual held work, but not from a map 

 already completed, so as to enable him to pass the 

 practical examination, say, of Sandhurst. Which 

 scale of the ordnance maps is most suitable for the 

 work, giving full information concerning elevation 

 above the sea, dip, etc. ? Also the best work on 

 microscopical rock sections, with illustrations, and 

 descriptions of the same ? He finds this branch of 

 the subject most bewildering to anyone taking up 

 geology for an examination. 



Thaxet Saxds. — In examining the Thanet 

 Sands in the cliffs between Heme Bay and Re- 

 culver, I have been struck by what appears to be a 

 similar structure in the sands to that in the chalk 

 beneath, in the shape of both vertical and 

 horizontal infiltrations of black crj^stalline silica, 

 The similarity in their mode of occurrence to the 

 flint veins of the chalk is most striking. They 

 appear to cross one another just like the flint 

 layers. It would be interesting to know whether 

 they have ever been seen to run continuously from 

 one formation to another, in sections where both 

 formations are exposed. Where the sand had been 

 quarried it was noticeable too that thin vertical 

 slabs of soft sandstone projected from the loose 

 matrix, being slightly indicated by an infiltration, 

 only, however, slightly so, since they crumbled 

 readily between the fingers. In the slabs the colour 

 was the same as that of the matrix. Bishopstone 

 Dell, a mile from Heme Bay, is apparently an old 

 water-course. The present ditch, as it is now, 

 about a hundred yards inland, can be but a much- 

 dwindled descendant of the stream which at one 

 time carved out the course and cut its way through 

 a thickness of fifty feet of Thanet sands. And yet 

 within a quarter of a mile, as one follows the course 

 inland, one rises to the level of the surrounding 

 country. Whence could arise, then, the velocity of 

 current necessary to carve out the dell ? This 

 seems to favour the theory which I have advanced 

 elsewhere, that there has been a local vertical 

 movement of the land here independently of the 

 process which resulted in the silting-up of the arm 

 of the sea which formerly existed at Reculver. I 

 have seen an engraving which shows half a mile of 

 land beyond the Reculver Towers. If the land 

 here remained quiescent, then the water-course for 

 this distance besides must have been carved by 

 water-power, and the stream must have been 

 proportionately larger. Going further back to 

 Roman times, when the town of Regulbium 

 flourished, the land still further extended into the 

 sea, and the water-course required still greater 

 force for its construction. I am therefore inclined 

 to suspect that the silting-up of the Wantsum is 

 not only due simply to fluviatile causes, but has 

 been assisted by an actual rise in the land. — Edivd. 

 A. Maiiin, Thornton Heath ; May, 1S96. 



Royal Meteorological Society. — A monthly 

 meeting of this society was held on Wednesday 

 evening, May 20th, at the Institution of Civil 

 Engineers, Great George Street, Westminster, Mr. 

 E. Mawley, F.R.H.S., President, in the chair. 

 Mr, R. H. Curtis, F.R. Met. Soc. read a paper on 

 the exposure of anemometers, in which he gave the 

 results of a comparison of the records from the 

 three anemometers at Holyhead, viz. : the Robin- 

 son, the bridled, and the pressure-tube anemometers. 

 It was clearly shown that the force of the wind is 

 greatly affected by surrounding objects. The 

 author is of opinion that for anemometrical records 

 to be reliable and of value, not only must the 

 instrument be exposed in an open place free from 

 local obstructions, but it is also absolutely essential 

 that the stand which carries it shall offer practically 

 no resistance to the wind, and that the instrument 

 should not be placed on the roof of a house. The 

 paper was illustrated by a number of lantern-slides. 

 An interesting collection of photographs of clouds, 

 sent to the society by Mr. H. C. Russell, F.R.S., 

 of the Sydney Observator}^ was also exhibited. — 

 The last meeting of this society for the present 

 session was held on the 17th, at the Institution, 

 Mr. E. Mawley, F.R.H.S., President, in the chair. 

 Mr. H. Harries read a paper on "Arctic Hail and 

 Thunder Storms," in which he showed that the 

 commonly-accepted opinion that hail and thunder 

 storms are almost, if not quite, unknown in the 

 Arctic regions is incorrect. He had examined one 

 hundred logs of vessels which had visited the 

 x\rctic regions, and found that out of that number 

 no fewer than seventy-three showed that hail was 

 experienced at some time or other. Thunder- 

 storms were not so frequent as hail, but they have 

 been observed in seven months out of the twelve, 

 the month of greatest frequency being August. 

 Air. Harries is of opinion that the breeding-place 

 of thunderstorms in these high latitudes is in the 

 neighbourhood of Barent's Sea. A paper by !Mr. 

 J. E. Cullum, on the " Climatology of Valentia 

 Island," was also read. The observatory at 

 Valencia, which is under the control of the 

 ^Meteorological Office, is situated on the extreme 

 south-west coast of Ireland, and is almost the most 

 westerly point of Europe. 



Norfolk and Norwich Naturalists' Society. 

 — The twenty-seventh annual meeting of the Norfolk 

 and Norwich Naturalists' Society was held in the 

 Castle ]\Iuseum on March 30th last, the President, 

 :\Ir. H. D. Geldart, in the chair. Sir F. G. M. 

 Boileau, Bart., F.R.S., F.S.A., was elected Presi- 

 dent for the coming session. The vice-presidents, 

 treasurer, honorary secretary, auditor, and journal 

 and excursion committees were re-elected. ^lessrs. 

 G. C. Eaton, E. Corder, and H. J. Thouless were 

 elected to serve on the committee in the place of 

 those retiring, in accordance with Law xv, 'Sir. 

 ?vIottram moved, on behalf of the committee, that 

 the dates of the meetings of the society be fixed 

 by the committee, and that Laws xxiv. and 

 XXV. be altered accordingly. This was carried 



