J^A TURE 



Sjfune 2, 1 88 1 



Platysomida had been derived from the Palaonisddir.—¥mf . 

 Tail communicated a number of results of experiments on the 

 heatin" effects of compression — experiments that had been sug- 

 gested°by his recent inquiry into Uie pressure errors of the 

 Challt-nger thermometers. Specimens of various substances, 

 such as raw potato, raw flesh, cheese, pith, bar-soap, liquorice, 

 cork india-rubber, &c., w ere compressed suddenly in a hydraulic 

 press. The rise of temperature was measured by means of a 

 thernioelectric junction set into the heart of the material, and 

 connected to a delicate galvanometer in a contiguous rocmi. After 

 the heat evolved by the compresMon had diffused itself, so that 

 the galvanometer came back nearly to its old zero, the pressure 

 •was'suddenly relieved, and the heat absorbed in the return of the 

 substance to its original bulk was measured by the reverse cur- 

 rent produced. In most ca es this cooling effect was exactly 

 equal to the original heating effect. Cork however, which rose 

 in temperature i°'3 F. for one ton's weight increase of pressure, 

 fell in temperature only o°-9 F. on removal of the pressure— a 

 result in striking accordance with the well-known sluggishness 

 of cork in recovering its original bulk after withdrawal of the 

 pressure that had compres-ed it. In this particular, india-rubher, 

 whose temperature was raised about i°'5 F. for the same increase 

 of pressure, was markedly opposed to cork. Potato and raw 

 flesh both indicated about the same rise of temperature— o°' 7 F. 

 Pith, again, which resembles the'-e in the large percentage of 

 water that enters into its constitution, was raised in temperature 

 only o°"37 F., giving no percepthle difference of effect overwhat 

 would have been produced by water alone. 

 Paris 

 Academy of Sciences, May 23. — M. Wurtz in the chair. — 

 The following papers were read :— On the old Observatory of 

 Cairo, by M. de Les^eps. This observatory no longer exists ; 

 but M. de Le-seps, in a letter here given, urges its restoration 

 on the Khedive. It is stated tnat the Egyptian Institute in 

 Cairo has received the Connaissame des Temps complete from 

 1679 to 1866. — Nebuloe discovered and observed at the Obser- 

 natory of Marseilles, by M. .Stephan.— On the genera William- 

 soitia Carruth., and Goniolina d'Orb, by MM. de Sap..rta and 

 Marion.— On an experimental process for determining the sensi- 

 bility of the retina to coloured luLuinous impressions, by M. de 

 Grandimont. The observer looks steadily at the central point of a 

 disk having apertures, beyond which coloured surfaces are placed. 

 By degrees the sensation of colour is extinguished. On sud- 

 denly putting white surfaces in place of the coloured, the com- 

 plementary colours come out with great brightness and purity. 

 The instrument is named a chromalroposcope.—^3xom>. ter based on 

 the equivalence of heal and pressure on the volume of a tjas, by 

 M. Decharme. It consists simply of an ordinary alcohol or 

 mercury thermometer, and an air themiometer to show the 

 volumes of gas corresponding to the temperatures observed. To 

 find the atmospheric pressure, the data of these instruments are 

 interpreted by the aid of curves and tables jireviously prepared. 

 — On a cryptogam insecticide, by M. Lichtenstein. This is a 

 Botrytis (same genus as that which mfests the silkworm), f ' .und to 

 have killed all 1 he aphidians on a cineraria in the Jardin des Plantes 

 at Montpellier. It operate^ only in the hothouse, and M. Lichten- 

 stein could not inoculate either phylloxera or other plant-lice with 

 it in open air. —On the geometry of spheres, by M. Stephanos. — 

 On Fuchsian functions, by M. Poincare.— The standards of 

 weights and measures at Paris Observatory and the apparatus 

 used in their construction ; their ori/in, history, and pre-ent 

 state, by M. Wolf This note relates chiefly to the toi. e du 

 Perou and du Nord (so called), which the author considers to he 

 now in the same state as when they came from the hands of 

 Langlois in 1735.— On the law of radiation, by M. Violle. This 

 lawmay be reiiresented between 0° and 1775° by the formula 

 /= niTb''-a^, where T^repre^ents the absohite temperature, m 

 a constant coefficient, l> the number 09999938, a= >'o355° - 

 13 \, \ being the wave-length in millimetres. — On the produc- 

 tion of sound by the force of radiation, by Prof. Ball.— On 

 radiophony ; thermophone reproducing the voice, by M. Mer- 

 cadier. Light is reflected from a plate of silvered glass, behind 

 which is a small air reservoir, with a thin plate of mica or caout- 

 chouc, which receives the voice through a tube. At the receiving- 

 end, one of the author's small glass tubes, withasmoked piece of 

 mica and ear-tube, is brought where the Hsjht is concentrated by 

 a lens or concave mirror. With this arrangement speaking was 

 distinctly, tliough faintly, heard at about 2om. distance, the 

 windows of the speaker's room being closed.— On the same sub- 

 ject, by the same. A long tube (lom.) may be used by the 



speaker. Electric light and (less easily) oxyhydrogen light, gave 

 the effects. Solar i-adiations act best when hottest. Alum solu- 

 tion interposed reduced the effects considerably ; with a thin 

 ebonite plate they were weakened, but still distinct ; simi- 

 larly with plates of tinsel of zinc, copper, aluminium, &c. , 

 ^mm. to TsVmm. thick. — Modification of the Neef interrupter 

 for the Ruhmkorff coil, by M. Ducretet. The vibrating slip is 

 lengthened and its two ends fixed to two columns ; the small 

 soft iron mass in the middle. The vibrations are very rapid ; 

 the spark is modified, becoming continuous, more powerful, and 

 hotter. — On the rotatory power of artificial codeine, by M. 

 Grimaux. — On the proportion of carbonic acid contained in the 

 air, by MM. Muntz and Aubin. This gives results of observa- 

 tion, by a method formerly described, at Paris and a station in 

 the country. They appear mainly to confirm M. Boussingault's 

 and M. Reiset's results. The proportions of COo in normal air 

 vary within but narrow limits. In the environs of Paris, what- 

 ever the direction of the wind, figures were got closely similar to 

 those of M. Reiset near Dieppe. — Preliminary study of reac- 

 tions without the mtervention of a solvent, by M. Lorin. — On 

 silicomolybdates, by M. Parmentier. — Action of ammonia on 

 chloride of isobmylene, liy M. Oeconomides. — On some points 

 relative to the organ'satl n and the development of Ascidians, 

 by M. Van Benedcn. This relates to his observations at the 

 Naples station in April last. The development of Ascidians 

 does not (he considers) warrant the radical distinction drawn by 

 the brothers Hartwig betw een a mesoderm and a mesenchyme. — 

 The vessels of the ink-bag of cephalopoda, by M. Girod. — On 

 the troubles of sensation produced by cortical lesions of the 

 brain, by M Couty. The observations were upon apes and 

 dogs. Anai'sthesia, when it occurs, affects the side opposite that 

 of the cortical lesion, and for touch, as for vision, is always in- 

 complete. It is rare, and it has no relation to the I'lace or 

 extent of the cortical lesion. These troubles of sensibility have 

 no necessary connection with other troubles. — Mechanism of 

 infection in different methods of inoculation of symptomatic 

 charbon ; application to the interpretation of clinical facts 

 and to the method of preventive inoculations, by MM. 

 Arloing, Cornevin, and Thomas. An abortive charbon may 

 be given by inoculaiion in the veins, in the connective tissue, 

 or in the respiratory passages. — M. Richard announced the 

 discovery of a cavern in the mountain of Ayuso (Segovia), 

 containing a large numbe- of prehistoric debris. 



CONTENTS Page 



Arctic EcHiNODERMATA 97 



Gkeek Geo.vietky 97 



Our Book Shelf:— 



"The Zoological Record for 1879" 98 



"Wiltshire Rainfall. 1880" 98 



Tegelmeier's "' Pheasants*' 99 



Kolberg's " Nach Ecuador" 99 



"Second Report of the United States Entomological Commission 



for the Years 1878 and 1879 " 99 



Laurentian Gneiss ot Ireland.— Prof. Edward Hull, F.R.S. . . IQO 



Resonance of the Mouth-Cavity.— Sedlkv Taylor 100 



Suggestion Relating to the Kew Standard Thermometers. — 



LhonaRD WALUi. ((i-y//i Z)ia.r?-awO 100 



" How to Prevent Drowning."— Win. Chappell ; Henry Mac- 



CokM-nC lOJ 



Optical Phenomenon.— James Ward loi 



An Optical lllusioa.—SAMUBLiDRKW loi 



Occurrence of Neolithic Implements at Acton, W.— Sfencer Geo. 



Pekcev«l >oi 



Bird- Singing during Thunder.— J. Shaw loi 



Fire-Halls -HENR^ O. Forbes 101 



Sound-Producing Ants.— Henry O. Forbes ........ ioi 



The Pitt-Rivers Collection: Bell-Clappers— the Tooth-Orn.iment. 



— Henuv O F.)KBES 102 



On Total Sola, Eclipses Occurring before the End of the 



Pke-ent Cknturv '02 



A Chapter in the History op the Conifer.^. II. By J. Starkib 



Gardner \ ' • • '"^ 



The «tokage of Electric Currents (With Illustrations) ... 105 

 A SijJGULAR Case of Shipwreck. By Capt. J. Allen Allen 



I IVith Illustration) ">" 



Noras "O? 



Our As rRONOMiCAL Column; — 



A New Variable Star ^^"^ 



The Comets of 1810 and 1863 (v) "' 



Chemical NoiHS ... "' 



Physical NoTBS " = 



Solar Phvmcs—Sun-Spots. By Prof. Balfour Stewart, F. R.S. 114 

 Prof. Allman ON the OavELOi-MENTOFTHE Ctenophora ... 117 

 UNivERsiry AND Educational Intblligencb "7 



Societies AND Academies . • • '^1 



