2o8 



NA TURE 



[July 2, 1908 



succession of maps is seen, the spectator is enabled to see 

 both processes in progress, viz. the march of the depression 

 and the course of the air in the various parts of the de- 

 pression. — .1/fs. Hcrtha Ayrton ; The residual motion .of 

 water moving in stationary waves. When a liquid rises 

 and falls in rhythmical wave motion its particles do not 

 simply swing to and fro, returning, like pendulums, to 

 their starting points after each oscillation, but each particle 

 takes up a new position after each oscillation, so that it 

 traces out a path for itself, only returning after many 

 oscillations to the point from which it started. This 

 general movement, which takes place in conjunction with 

 the oscillatory movement, is called the residual motion of 

 the liquid. It takes the form of vortices of peculiar shape, 

 which are exactly the opposite of the ripple-forming vortices 

 to which obstacles under the water give rise, since a single 

 residual vortex is only completed in many oscillations, while 

 each ripple-forming vortex is born and dies in a single 

 swing. 



Prof. A. M. Worthingtoii, C.B., F.R.S.: Recent instan- 

 taneous photographs of splashes. — Dr. W. J. Russell, 

 F.R.S., and Mr. U. F. Block: Photographs of flowers, &c., 

 in natural colours (Lumi^re process). — Mr, H. G. King and 

 Mr. R. Kerr: "Master gauges" or "standards" for 

 extremely accurate measurements, the invention of Mr. 

 C. E. Johansson, of Sweden. By using these gauges 

 separately or combined together, more than 80,000 different 

 sizes can be obtained, any of which sizes are accurate 

 to within 0^00004 inch at 66° F. The steel is so treated 

 as to reduce to a minimum any chance of change after 

 being hardened. The gauges are used where extreme 

 accuracy is required, as in the manufacture of machine 

 parts, tools, and various instruments; also for "marking 

 off '.' dies on surface plates and for testing them when 

 machined, &c. Two of these blocks put face to face can 

 sustain a pull of iij lb., or 22 lb. to the square inch. — 

 Mr. Frederick lies: (i) " Irisographs," or chemical 

 designs. " Irisography " is a method of producing 

 coloured designs by means of chemical solutions applied in 

 spots upon unsized paper, and subsequently developed by 

 the central application of a compound solution which, 

 spreading by capillary attraction, and coming into contact 

 with the previously applied spots, combinss with and 

 reacts upon them to produce designs of varied outlines and 

 colours. (2) " Caleidographs." Original designs executed 

 by aid of the caleidograph on china, glass, paper, and on 

 prepared glass plates. The " caleidograph " is an instru- 

 ment to facilitate the working out or elaboration of simple 

 or complex designs composed of geometrical curves and 

 lines, either upon paper or on the actual articles of china, 

 glass, metal, &c. 



Dr. J. A. Fleming, F.R.S. : Transmission of signals bv 

 electromagnetic induction between oscillatory circuits, and 

 their reception by means of a glow-lamp detector. At one 

 end of the principal library a square circuit was set up 

 in which high-frequency oscillations were created by the 

 discharge of a Leyden jar charged by an induction coil. 

 The coil was actuated by a coal-gas mercury break, and 

 the spark was in a silencing chamber with air-blast arc 

 destroyer. The oscillations were cut up into Morse signals 

 by a punched tape and relay in the primary circuit. One 

 hundred feet away was a similar receiving circuit, in 

 which oscillations were created by induction transmitted 

 from the sender, and were detected by a glow-lamp detector 

 or oscillation valve and telephone. Messages and signals 

 thus sent formed a small-scale exhibition of high-frequency 

 inductive wireless telegraphy. — Dr. Alexander Muirhead, 

 F.R.S. : A combined Kelvin siphon recorder and cable 

 relay. The latest form of the Kelvin siphon recorder has 

 bi ;>n converted into a successful cable relay by simply sub- 

 stiluting fine srold wire for the silk fibre which connects 

 the siphon to the vibrator. 



Mr. Leonard Hill, F.R.S.: (j) Self-contained diving 

 dress (made by S-Iessrs. Siebe, Gorman and Co., Ltd.). 

 .■Xir-pump, pipe, and life-line are done away with, and the 

 diver is connected to the surface by a telephone cable only. 

 .Attached to the back of the ordinary diving dress are 

 cylinders containing air with Jo per cent, oxygen. The 

 oxvgen mixture is delivered to the helmet bv a pipe, to 

 which n reducing valve is attached. The suppiv is 4 litres 

 per minute, and lasts two hours. Two caustic £_^da boxes 



NO. 201S, VOL. 78] 



are connected by a pipe with the helmet, and by a second 

 pipe to an aspirating arrangement placed in the oxygen 

 delivery tube. The lorce of the oxygen mixture escaping 

 through a narrow jet is used to aspirate the air in the 

 helmet through the soda boxes, which purify it from the 

 exhaled carbonic acid. (2) Life-saving apparatus for use 

 in mines (made by Messrs. Siebe, Gorman and Co., Ltd.). 

 The apparatus, perfected out of that of Mr. Fleuss, consists 

 of a breathing bag, and cylinders of compressed oxygen, 

 carried by straps passing over the shoulders, and so hung 

 that the man is free to do work. The dress allows the man 

 to be stripped to the waist in hot atmospheres. — Prof. 

 Arthur Gamgee, F.R.S. : Photographs, drawings, and plans 

 exhibiting the apparatus employed by Prof. Gamgee in his 

 research on methods for the continuous (photographic) and 

 quasi-continuous registration of the diurnal curve of the 

 temperature of the animal body. 



Dr. G. H. Rodman : .\ series of stereoscopic radiographs 

 of molluscal shells. Prior to the application of the Rtintgen 

 rays to this branch of zoological research, it was necessary 

 to sacrifice the specimen in order to disclose the internal 

 anatomy of the columella and whorls — a course obviously 

 undesirable in the case of a rare and possibly unique shell. 

 In some of the examples shown the radiograph has been 

 so made as to show the equivalent of both horizontal and 

 vertical sections. — Mr. H. $. Leigh : Living examples of 

 the leaf insect from the Seychelles, Phylliuni cnirifoliitm, 

 Serville. The Phylliums afford one of the most striking 

 e.xamples of protective resemblance. The specimens are not 

 only very similar to leaves in shape and colour, but in their 

 peculiar movements imitate the shaking of the leaves. The 

 resemblance to vegetable structures is carried still further, 

 since the eggs bear a marked likeness in shape and colour 

 to certain seeds. — Prof. J. Cossar E-Mart, F.R.S. : Hybrid 

 between a Prejvalsky mare (_Eqnus prejvalskii) and a High- 

 land pony. This is one of six hybrids bred from wild 

 horses imported from Mongolia. With the exception of 

 the one exhibited, the hybrids are out of pony mares. All 

 six hybrids are males, and two foals out of pony mares 

 by a hybrid bred at Penycuik in 1905 are males. The 

 hybrids support the view that a wild horse of the Prejvalsky 

 type took part in the making of domestic horses. Four 

 of the six hybrids were bred at Woburn by his Grace the 

 Duke of Bedford. — Mr. F. Knock : Insect intelligence, as 

 exemplified in the life-history of the wood-boring wasps 

 (Crabronida:). .\\\ hymenopterous insects show a high 

 degree of intelligence. One species of Crabro fills its cells 

 with one, and only one, species of insect ; another with 

 one kind of beetle ; a third with homopterous insects. 



Dr. A. S. Woodivard, F.R.S.: Photographs, by Mrs. E. 

 von Kaufmann, of portions of carcases of a mammoth and 

 rhinoceros found preserved in petroleum at Starunia, 

 Galicia. These specimens were obtained in an ozokerite 

 mine while sinking a shaft through the deposit of an old 

 marsh which was saturated with petroleum. — The Director- 

 General. Survey Department, Egypt : Plans, photographs, 

 and objects illustrating the archicological survey of that 

 portion of the Nile Valley which will be submerged by the 

 Aswan reservoir when its level is raised. A detailed survev 

 of the valley and the ancient sites is being made, and the 

 anatomical study of all human remains found is being 

 carried on simultaneously with the arch.cological investi- 

 gations. Numerous pre-dynastic cemeteries have been 

 found, and the present evidence shows that in these times 

 Lower Nubia and Egypt formed one ethnological terrilorv, 

 both districts being in the same state of culture. From 

 the first dynasty their history diverges ; in Egypt the race 

 remains unchanged, and culture shows a progressive 

 development ; in Nubia the race becomes mixed with a 

 strong infusion of negro blood, and culture lags behind 

 that of Egypt. — Miss M. Helen Tongue: Bushmen paint- 

 ings copied by the exhibitor from the caves and rocks in 

 Cape Colony, Orange River Colony, and Basutoland. The 

 paintings, which are found on the walls or roofs of rock 

 shelters or caves, generally in sandstone districts, have been 

 coloured with iron oxides, or with ochres mixed with f.-n. 

 The date of the work varies. In Cape Colony the lati:.t 

 paintings must be nearly a century old. In Basutoland 

 there may be some of a later date ; probably most arc older. 

 The pictures have been carefully traced, and the colours and 

 background copied as exactly as possible. 



