450 



NATURE 



iMarch lo, 1881 



cially in the vicinity of Ujiji, they are both more common and 

 more severe than at the coast. Shortly after the cable w r>s laid 

 between Mozambique and Pelagoa Bay, the communication was 

 suddenly interrupted after one of these earthquake shocks, ^^ liich 

 seems to have caused the falling in of rocks by which the calle 

 was crushed." — The Permian, Triassic, and Liassic rocks of '.he 

 Carlisle Basin, by T. V. Holmes, F.G.S. The district .lis- 

 Cussed in the author's paper was worked over by him when 

 engaged on the geological survey, and consists of those pans it 

 Cumberland and Dumfriesshire which adjoin the Solway. Its 

 southern boundary is, approximately, a line ranging from Mary- 

 port to Rose Castle on the River Caldew, and touching the Eden 

 about two miles above Wetheral. On the east and noiih-east 

 its limits are the immediate neighbourhoods of the junction of 

 the rivers Eden and Irthing, Ilethersgill on the Hether I'urn, 

 Brackenhill Tower on the Line, and the border boundarj- on the 

 Rivers Esk and Sark ; and in Dumfries-^hire the small tract 

 south of a line ranging from the junction of Scots Dyke with tlie 

 Sark on the north-east, to Cummertrees on the south-west. 

 The lowest bed in this area is the great Upper Permian or St. 

 Bees Sandstone, which occupies a belt of country in the neigh- 

 bourhood of the outer boundary. Directly above St. Bees 

 Sandstone, in the west of the district, lies a formation consisting 

 of shales with gypsum, which, though 700 feet thick in i!u- 

 neighbourhood of Abbey Town, is nowhere visible, but is know n 

 solely from borings, the country west of the Caldew, ard i f the 

 Eden below the junction of the two streams, being thickly drilt- 

 covered and almost sectionless. In the e.ast of the district the 

 St. Bees Sandstone is overlain directly by a soft, retl, false-beiided 

 sandstone, called by the .luthor Kirklinton Sandstone, from the 

 locality in which the rock is best seen, as w ell as its relations to 

 the under- and overlying beds. But while there is no evidence 

 of .any unconformity between the St. Bees Sandstone and the 

 overlying Gypseous Shales in the west, there is evidence of a 

 decided unconformity between the St. Bees and Kirklinton 

 S.andstones in the east. In Carwinley Bum (for exaniplei, 

 which runs into the Esk at Netherby, only from 200 to 3C0 feet 

 of St. Bees Stone wtis seen below the outcrop of the Kirklinton, 

 instead of the looo to 1500 feet which probably exist about 

 Brampton on tlie one hand, and in Dumfriesshire on the other. 

 Yet Carwinley Bum aflbrds an almost continuous series of sec- 

 tions, from the (non-faulted) Permian-Carboniferous junction to 

 some distance above the outcrop of the Kirklinton Sandstone. As, 

 in addition, the >hales underlying the St. Bees Sandstone sre 

 gypseous, both ne.ir Carlisle and at Barrowmouth, close to St. Bees 

 Head, the .author classed the ^Vpper) Gypseous Shales as Permian, 

 and the Kirklinton Sandstone as Bunter. Resting unconformahly 

 on the Kirklinton .Sandstone, in the district between Carlisle nnd 

 Kirklinton, are the Marls seen on the Eden, between Stanw ix 

 and Beaumont, and on the line between We-tlinton and Cliff 

 Bridge, Kirklinton. Their unconformity is shown by the fact 

 that on the line they rest on the low er, or red, beds, and between 

 Stanwix and Be.iumont on the upper, or white, beds of the Kirk- 

 linton Sandstone. The Marls have therefore been classed as 

 Keuper. So far as the evidence goes they appear to be very 

 thin, and to extend but a very small distance soutli of the Eden. 

 Lastly, the Lias appeared to the author to be unconformable to 

 all the beds below-, and to rest partly on the Gypseous Sh.-\les, 

 partly on the Kirklinton Sandstone, and partly on the Keujer 

 Marls. Of the existence of Khxtic beds there was no evidence, 

 all fossils hitherto found having been determined by Mr. 

 Etheridge (the president) to be Lower-Lias forms. But the Lias- 

 sections are so small and few in number, and the ground so per- 

 sistently drift-covered, that only a boring could settle the 

 question. — On Astiwoma Granti, a new Lyssakine Hexactinellid 

 from the Silurian formation of Canada, by Prof. W. J. SoUas. 

 M.A., F.G.S. This p.iper contained a description of a new- 

 fossil Hexactinellid sponge from the Ni.agara chert beds of 

 Hamilton, Ontario. It is the second oldest known example of 

 the Lyssakina. 



Anthropological Institute, February S.—Major-General A. 

 Pitt-Rivers, F.R.S., president, in the chair.— The election of 

 the following new members was announced : A. G. Geoghegan, 

 E. H. Man, Owen Roberts, and Bruno Miiller.— Mr. W. L. 

 Distant exhibited some Carib chisels from Barbadoes, which had 

 been sent to him by Mr. W. J. SoUas, of Bristol. They were 

 t.aken with about 100 more from a cave, and were found six or 

 eight inches below tlie surface. The cave is about 350 feet 

 above the sea level, and is situated at a distance of two miles 

 from the coast. — Mr. A. L. Lewis read a paper on two stone 



circles in Shropshire. Between five and six miles west of 

 Minsteily is a circle of small stones known as the " Ho.arstone." 

 The Largest stone is in the centre and is surrounded by thirty- 

 three stones and fragments aiTanged in a circle about 74 feet in 

 diameter. -■Vbont a mile and a half in a south-westerly direction 

 from the Hoarstone is another circle ciUed in Gough's " Camden's 

 Brit.annia" "Madge's Pinfold.'' Here thirteen stones and three 

 fragments stand and lie in an oval ring, the diameters of which 

 are about So feet and 92 feet, the longest diameter running 

 north-west and south-east. — Miss A. W. Buckland read a paper 

 on surgery and superstition in neolithic times ; the object of 

 which was to bring before the Institute the frequent use of 

 trepanning in Xeolithic times, as proved by the late Dr. Broca ; 

 to call attention to the proofs he has given of the facts, and to 

 his explanation of the reason of the practice, and of the super- 

 stitions associated with it, as also its connection nitli the use of 

 cranial amulets. 



Physical Society, February 26. — Prof. Fuller in the chair. 

 The former resolution regarding the moneys of the Society 

 for investment was adopted. — Dr. O. J. Lodge exhibited a 

 mechanical apparatus illustrating the fact that conductors of 

 electricity are opao,ue to light, and showed by means of a 

 Wheatstone's photometer, which combines two circul.ar motions 

 into a harmonic one, how the plane of polarisation of a beam of 

 light passing through a magnetic medium is rotated. — Mr. C. V. 

 Boys exhibited his new integrating machine, which is tlie only 

 one illustrative of the mathematical process of integration, and 

 is therefore specially valuable for teaching purposes. — Mr. 

 Shelford Eidw ell read a paper on the telegraphic transmission 

 of pictures of natural objects. The process is explained as 

 follows : — The positive pole of a batteiy is connected through a 

 set of resistance-coils to a piiece of platinum wire, and the 

 negative pole to a plate of zinc, upon which is placed a sheet of 

 paper moistened with a solution of pot.issium iodide. The 

 negative pole of a second battery is connected through a sele- 

 nium cell with the same platinum w ire, and the positive pole to 

 the zinc plate. The point of the platinum w ire is pressed upon 

 the paper, and the selenium being exposed to a strong light, the 

 variable resistance is so adjusted that the cm-rents fr.ni the t^vo 

 batteries w hich pass through the paper in opposite directions 

 exactly neutralise each other. The platinum point will now 

 make no mark when drawn over the paper ; but if the selenium 

 is shaded, its resistance is immediately increased : the current 

 from the first battery then predominates, and the path of the 

 platinum point across the paper is marked by a brown line due 

 to the liberation of iodine. The line is fainter the feebler 

 the light is. This arrangement has been applied by Mr. 

 Bidwell in his " telej holograph," exhibited to the meet- 

 ing. The transmitter consists of a brass cylinder mounted 

 on a screw- spindle which carries the cylinder laterally 5*1 inch at 

 each revolution. A pin-hole in the middle of the cylmder allows 

 light to fall upon a selenium cell \ laced behind it within the 

 hollow cylinder. The cell is connected in circuit with a battery 

 and the line. The receiver consists of a siniil.ar metal cylinder 

 mounted so as to rotate synchronously w ith the first, and having 

 a platinum point pressing upon a sheet of chemical paper 

 wrapped round the cylinder. This receiver and transmitter are 

 connected up as described above with two batteries and a set of 

 resistance-coils. The image to be transmitted is focussed upon 

 the cylinder of the transmitter and the resistance adjusted, and 

 the receiving cylinder covered with sensitised papei". The two 

 cylinders are caused to rotate synchronously, the pin-hole in the 

 course of its spiral path covering successively every point of the 

 focnssed picture. The amount of light f.-Uling upon the selenium 

 will be proportional to the illumination of that particular spot of 

 the projected image which is for the time being occupied by the 

 pin-hole, and the intensity of the line traced by the platinum 

 point in the receiver will vary in the s,ame ) roportion. These 

 variations will produce a picture which, if the instrument were 

 perfect, would be a counterpart of that projected upon the 

 transmitter. Simple designs cut out of tinfoil and projected 

 by a lantern have been successfully transmitted. With 

 selenium and paper of greater sensitiveness more perfect 

 results might undoubtedly be obtained. — Professors Ayrton 

 and Perry showed an experiment illustrating their plan for 

 sending light and shade images by electricity. A selenium 

 cell was connected in circuit with a battery and a coil of wire 

 surrounding a tube along which a beam of light passed. A 

 shutter having a small magnet attached was suspended in the 

 tube like a gah-anometer mirror, so that when a current traversed 



