3<5° 



NATURE 



[Fed. 12, 1880 



resembles, intended for the optical study of sounds. A complete 

 description of the instrument is not, however, given. 



According to Herr H. Schwarz, an admirable cement for 

 glass, ami one which completely resists the solvent action of 

 water, may be prepared by the following process : From 5 to 10 

 parts of pure, dry gelatin are dissolved in too parts of water. 

 To the solution about 10 per cent, of a concentrated solution of 

 bichromate of potash is addtd, and the liquid is kept iu the dark. 

 When articles joined by means of this cement are exposed to the 

 light the gelatine film is acted upon by the chemical rays, the 

 chro mate heing partially reduced, and the film of cement becomes 

 extremely tough and durable. 



The "meter" devised by Edison for his system of domestic 

 electric lighting depends upon the electro-deposition of copper 

 upon an electrode in a branch circuit whose resistance bears a 

 know 11 ratio to that of the circuit of the user, the movable copper 

 electrode being weighed at stated intervals in order to gauge the 

 Consumption. There is also in the "meter "a most ingenious 

 contrivance whereby if any consumer draw too largely on the 

 supply the armature of an electromagnet in the circuit is attracted 

 and " cuts out " the transgressing consumer, actually fusing up the 

 only remaining metallic connection! 



Lippmann's principle that if by mechanical means we deform 

 a mercur) surface, an electrical liberation is produced which 

 tends to arrest the movement of ihe mercury, has led M. Debrun 

 to contrive an apparatus (Jour, de Phys., January) in which 

 mercury is admitted in drops, with acidulated water between, 

 down a conical tube, into a vessel arranged as a Florentine 

 receiver (giving separate outflow to the two liquids). The upper 

 and lower masses of mercury are connected with platinum wires, 

 which take their polarity, and a current is found to proceed in 

 the direction of the globules. With a tube 0*30 m. long, 

 2 - 5 mm. diameter at top, and I mm. at the lower part, and 

 containing at least twenty mercury globules, and not more than 

 thirty-five, the electromotive force is about I '4 volts, giving 

 decomposition of water with Wollaston points. Only 2 kg. of 

 mercury are expended in the hour. Letting the mercury flow 

 twenty-four hours, M. Debrun was able to silver strongly a 

 five-centiuies piece. Several experiments may be made with the 

 apparatus ; thus if the poles are disconnected the mercury flows 

 slowly and difficultly, but when they are connected it flows very 

 rapidly. 



A NEW galvanic battery with circulating liquid, described by 

 Signor I'onci in Natura (3, p. 402, 1S79), has the following 

 form : — Rectangular lead channels, beak-shaped at one end, are 

 so placed over one another in slanting position that thi beak of 

 the first is over the broad end of the second, and so on. In each 

 chann 1 i an amalgamated zinc plate, and above this a carbon 

 plate insulated from it by two rings of caoutchouc ; the carbon 

 plate is perforated under the beak of the lead channel above. 

 The had channels have wires, and the carbon plates, at their 

 upper ends, binding screws, with which they are alternately con- 

 nected. By means of a caoutchouc siphon a solution of chromate 

 of potash is conducted through the system (200gr. K„Cr.,0 7 , 

 21 water, II commercial muriatic acid ; for long use 3 to 6 litres 

 water and 100 to 150CCU1. muriatic acid may be added to each 

 litre of the solution). A battery of 99 such elements gives a 

 light-arc equal to that of a battery of 60 Bunsens, and is constant 

 in duration. 



The following reaction, proposed by M. Jorissen, for disco- 

 vering very weak traces of morphine, is reported by M. Donny 

 (Bulletin of Belgian Academy) to be very sensitive. The 

 morphine is treated first with sulphuric acid, then with ferrous 

 sulphate ; a nearly colourless liquid is thus obtained, but on 

 letting it fall drop by drop into concentrated ammonia, a very 

 intense blue- purple coloration is inline iately produced. 



GEOGRAPHICAL NOTES 

 At the meeting of the Geographical Society on Monday 

 evening, the Earl of Northlirook announced, amidst great 

 applau e, that Colonel Gordon had been elected an Honorary 

 Corresponding Member, and at the same time passed a high 

 eulogium on his character and his services in Egypt and else- 

 where. Major-Gen. Sir M. A. S. Biddulpb, K.C.B., who 

 commanded a column in the last Afghan campaign, afterwards 

 read a paper on the eastern border of Pishin and the basin of 

 the Loras. The country dealt with had never previously been 



examined by Europeans, all our information having been derived 

 from native sources, and consequently the particulars so labori- 

 ously collected by Sir M. Biddulpb, w ith the aid of the survey 

 officers acting under him, will prove of the utmost value to 

 cartographers. He mentioned several instances in which our 

 present maps are entirely wrong, specifying one in which the 

 position of a place would have to be shifted fifty miles. A 

 peculiar characteristic of the country examined was the existence 

 of long plains in the valleys, which rendered movement com- 

 paratively easy, another being the great number ol water-partings. 

 The basin of the Loras, — a name given to all streams in that 

 region, — consists, in fact, of a curiously involved system of 

 mountain ridges, about which Sir M. Biddulph furnished much 

 valuable topographical information. 



At a committee meeting of the German African Society at 

 Berlin, at which Dr. Gerhard Rohlfs was present, it was resolved 

 to recommend Dr. Stecker to continue the expedition to Wadai, 

 by way of Mursuk, Bornu, and Adamauk, as on this route he 

 will travel under the protection of the Khedive of Egypt. 

 According to the opinion of Dr. Rohlfs it is beyond all doubt 

 that the Turkish government will fully compensate the Society 

 for the loss sustained through the attack upon the expedition. 



The Vega left Port Said on the Gthinst., and may be expected 

 to reach Naples to-day. 



The new number of the Annates def Extreme Orient contains, 

 among other mitter, a paper on the languages and literature of 

 Java, by Prof. P. J. Veth, President of the I hitch Geographical 

 Society, notes on recent Dutch explorations in New Guinea, and 

 some remnrks on Lieut. Delaporte's work, entitled " Voyage au 

 Cam bodge." 



Mr. Alexander Forrest contributes to the December 

 number of the Victorian Review, published at Melbourne, a very 

 interesting, though somewhat brief account of bis explorations 

 during his recent journey from Perth, Wet Australia, to Port 

 Darwin, in the Northern Territory. \\ e believe that Mr. Forrest 

 is very sanguine that large tracts of the fertile country which he 

 has discovered will shortly be taken up and occupied by settlers. 



The last number of the Proceedings of the Asiatic Society of 

 Bengal contains a paper on the exploration of the Great Sanpo 

 River of Tibet, by Major-Geneial J. T. Walker, which is 

 illustrated by a map. Capt. W. E. Gowan also furnishes a transla- 

 tion from the Russian of the geographical information regarding 

 the Kirghiz Steppes and country of Turkistan, afforded by the 

 Book of the Great Survey. 



Writing to Les Missions Catholiques from Landana, in 

 Congo, Pere Carrie supplies a fen particulars respecting Mr. 

 H. M. Stanley's expedition from the west coast, about which 

 the International African Associa i n has been remarkably 

 silent. Mr. Stanley, it appear , has with him fourteen white 

 men, one Arab, two natives of Sierra Leone, and sixty-one men 

 from Zanzibar, whence a large additional number are shortly 

 expected to arrive in charge of a European. Pere Carrie adds 

 that Mr. Stanley has already established a station at NoUi, some 

 miles above Mboma. He has with him a number of wooden 

 houses all ready for erection at vari >us points as he advances into 

 the interior. 



As the result of fifteen years' re-earch into the archaeological 

 riches of Hainault, M. Theodore Bernier has just published 

 (Monsj H. Maneraux) a volume entitled " Dictionnaire Geo- 

 graphique, Historique, Archeologique, Biographique, et Biblio- 

 graphique du Hainault." 



In connection with Mr. G. J. Morrison's paper on the Grand 

 Canal, read before the Geographical Society on January 12, 

 much interest attaches to a letter in the North China Herald, 

 from its Tientsin correspondent, whose experiences are about 

 eighteen months later. Being desirous of going to Te-chow, in 

 Shantung, he made the journey by the Grand Canal The water 

 in the Pei-ho at the time was higher than it had been for nearly 

 ten years, but the Canal had'risen but slightly, the water coming 

 mainly from the streams to the south-west. On the second day, 

 however, a sudden rise was apparent, the water wanting but an 

 inch or two of overflowing. Still little effort was made to guard 

 against danger ; a few weeds or kao-liang (millet) stalks covered 

 with earth, or simply a few shovels-full of earth in many cases, 

 were the only defence against the rising water. To the west of 

 the Canal was a vast expanse of flooded c .untry, stretching for 

 100 miles or more. At one place where the bank was weak. 



