Nov. 15, 1883] 



NA TURE 



n 



Professorship of Rural Economy will not be a resident one. 

 The Professor will have to deliver twelve lectures. His stipend 

 is 200I. a year. 



SOCIETIES AND ACADEMIES 

 London 

 Mathematical Society, November 8. — Prof. Henrici, 

 F.R.S., president, in the chair. — The following resolution, pro- 

 posed by the President and seconded by Dr. Hirst, F.R.S., was 

 carried unanimously, viz.: — "That the secretaries be requested 

 to communicate to Mrs. Spottiswoode the expression of our sin- 

 cere sympathy and the assurance of our deep .sense of the loss 

 which science has sustained by the untimely death of Mr. 

 Spottiswoode." — The new Council was elected for the session 

 1883-84, viz. : Prof. Henrici, president; Sir J. Cockle, F.R.S., 

 and Mr. S. Roberts, F.R.S., vice-presidents; Mr. A. B. 

 Kempe, F.R.S., treasurer; Messrs. M. Jenkins and R. Tucker, 

 honorary secretaries; other members. Prof. Cayley, F.R.S., 

 Messrs. E. B. Elliott, J. W. L. Glaisher, F.R.S., J. Hammond, 

 H. Hart, Dr. Hirst, F.R.S., W. D. Niven, F.R.S., Prof. 

 Rowe, and Messrs. R. F. Scott and J. J. Walker, F.R.S. The 

 Rev. [. J. Mylne and Mr. F. W. Watkin were elected members. 

 — The foUouing papers were communicated : — Symmetric func- 

 tions, and in particular on certain inverse operators in connection 

 therewith, Capt. P. A. Macmahon. — On a certain envelope. 

 Prof. Wolstenholme. — On certain results obtained by means of 

 the arguments of points on a plane curve, R. A. Roberts. — Third 

 paper on multiple Frullanian integrals, E. B. Elliott. — Note on 

 Jacobi's transformation of elliptic functions, J. Griffiths. — Sym- 

 medians and the triplicate-ratio circle, R. Tucker. 



Linnean Society, November l. — Frank Crisp, treasurer 

 and vice-president, in the chair. — Messrs. T. E. Gunn and A. 

 Hutton were elected Fellows. — A donation to the Society of 

 several interesting letters of Linnaeus (1736-1769) to G D. 

 Ehret, F.R.S., an eminent botanical artist of the last century, 

 was announced by the Chairman, and a unanimous vote of 

 thanks thereupon accorded to the Misses Grover and Mr. Chas. 

 Ehret Grover for their valuable donation. — Mr. Crisp drew 

 attention to specimens in fluid medium of Limnocodiiim sow/rhii, 

 as illustrative of Mr. P. Squires' method of preserving delicate 

 and other medusae. — Mr. H. Groves showed examples of Chara 

 braunii from Ashton-under-Lyne, and Mr. Arlhar Beimett of 

 Najas marina and N. alagnensis from Hickling Broad, Norfolk, all 

 being new to the British flora. — Mr. W. Fawcett exhibited Testa- 

 cella maugei alive, the same being obtained by J. C. Mansel Pley- 

 dell in Dorset, and supposed to be indigenous to that county. — A 

 paper was read on the changes of the flora and fauna of New Zea- 

 land, by Dr. S. M. Curl. He referred more particularly to the 

 district of Rangitikei and to the alterations of the aspect of the 

 vegetation within the last forty years. He likewise records his 

 own experiments in the cultivation of trees, shrubs, and flower- 

 ing plants introduced from widely different climes, remarking 

 that while a few fail to grow with vigour, the majority by 

 degrees adapt themselves to the altered conditions, and many 

 valuable economic plants thrive accordingly. — Mr. J. Starkie 

 Gardner read a paper on Alnus richardsom, a fossil fruit from 

 the London Clay of Heme Bay. The species has been de- 

 scribed by Bowerbank and commented on by Carruthers, 

 Ettinghau^en, and many other avithors who have written upon 

 the plants of the Tertiary formation. Originally considered as 

 allied to Casuarina, Dr. R. Brown suggested its affinities to 

 the Proteacece, a view afterwards upheld by Carruthers and 

 others. Ettinghausen thereafter regarded it as a product of a 

 Conifer (Scyiioi'a), and Saporta compared the fruit to that of 

 Dammara, Mr. Gardner enters fully into the structural pecu- 

 liarities of the fossil fruit in question, and sati--factorily dem m- 

 strates that it belongs to the Betulacese under the gmus Alnus. 

 — Another paper by Miss G. Lister was read, viz. on the origin of 

 the Placentas in the tribe Alsine* of the order Caryojihylleas. 

 This communication is based on a series of observations on the 

 development of a number of genera and species. She concludes 

 that the capsule in the Alsinex is developed on essentially the 

 same plan as that of Lychnis^ the difference in the vari >us genera 

 being merely dependent upon the relative height attained by the 

 carpels on the one hand, and by the central axis on the other. 

 This being so, we are bound to admit that if we acccp', as we 

 do, the carpellary origin of the placentas in Lychnis, the pla- 

 centas in the Alsineae, from Sagina apetala, which nicjst resemble 



Zi chnis, to Ccraslium triviale, which most widely differs from it, 

 are also carpellary. 



Chemical Society, November i. — Dr. Perkin, F.R.S. , 

 president, in the chair. — The f illowing papers were read : — On 

 the production of hydroxylamine from nitric acid, by E. Divers. 

 Free nitric acid yields hydroxylamine when treated with tin, 

 zinc, cad ninm, magnesium, and aluminium. In the presence of 

 hydrochloric or sulphuric acid the quantity with tin or zinc may 

 be con^ider.able. Without a .second acid only traces can be 

 detected. The author also discusses the action of nitric acid 

 upon metals and the constitution of nitrites, in which he con- 

 siders the metal to be directly united with nitrogen. — On the 

 chemistry of lacquer (Urnski) (part i.), by H. Yoshida. Lacquer 

 contains a peculiar acid, Urushic acid, extracted by alcohol. Some 

 gum resembling gum arable, water, and a peculiar diastatic body 

 containing nitrogen. The lacquer when exposed to moi^t air at 

 20' C. dries up into a hard lustrous varnish. This hardening is 

 brought about by the action of the diastase upon Urushic acid, 

 the latter being converted into oxy-urushic .acid. — On some com- 

 pounds of phenols with amidobases, by G. Dyson. The author 

 has prepared and investigated anilin phenate, toluidin phenate, 

 naphthylamin phenate, anilin /3 naphthate, toluidin naphtnate, 

 rosanilin phenate, xylidin naiihthate, rosanilin aurinate, anilin 

 aurinate. — On the alleged decomposition of phosphorous anhy- 

 dride by sunlight, by R. Cow|jer and V. B. Lewes. In a paper 

 at the British Association, Southport, the Rev. A. Irving stated 

 that phosphorou- anhydride prepared by passing air over heated 

 phosphorus is decomposed by sunlight into phosphorus and 

 phosphoric anhydride. The authors find that I'hosphorous 

 anhydride thus prepared consists of a mixture of phosphoric 

 anhydride, phosphorous anhydride, and phosphorus. 



Physical Society, November 10. — Prof. Clifton in the 

 chair. — Dr. J. Blaikley read a paper on the velocity of sound in 

 air, ill which he described a modification of Dulong's method of 

 measuring it by the wave-length in a pipe lengthened. Dulong 

 did not allow for the partial tones, which are an important 

 factor, whereas Mr. Blaikley does. By means of organ pipes of 

 different diameters, the author has found the velocity to be 

 about 320 metres per second. Mean result with four tubes : 

 oneof 54'i mm. diameter, velocity = 32g'73metres per second ; 

 one of 32"5 mm. diameter, velocity = 32878 metres; one of 

 I9'5 mm. diameter, velocity = 3269 metres ; one ol II'7 mm., 

 velocity = 324 '56 metres. The velocity diminishes as the tube 

 is smaller in bore. — Mr. Bo^anquet made a communication on 

 the moment of a compound magnet, which he showed how to 

 measure by the method already pulilished by him. A compound 

 magnet made up of eighteen small cylinders of magnetised steel 

 placed end to end is hung in a cradle carried by a delicate bifilar 

 suspension, and placed at right angles to the magnetic meridian. 

 The deviation from zero produced by the magnet is noted ; then 

 the magnet is divided into two parallel rows of nine cylinders 

 along the cradle, and the deviation again noted. The tangent 

 of the angle of deviati m from the east and west line, multiplied 

 by a constant, is the monent of the magnet. The author also 

 pointed out that to define the condition of a permanent magnet 

 it was neces-aryto know the d fference of magnetic potential, the 

 " resistance " of the metal, and the resistance of the external space. 

 — Mr. W. Lant Carpenter read a paper on measurements relating 

 to the electric resistance of the skin, and certain medical ap- 

 pliances. The author's experiments, made upon himself, showed 

 that the resistance of the body amounts to thousands of ohms, 

 but is mainly due to the condition of the epidermis. If this is 

 dry, the resistance is high By soaking the skin in salt and 

 water, he reduced the re-istance of parts of bis body from 

 10,300 ohms t . 935 ohms after 100 minutes' soaking. He infers 

 th.at a large electrode should he used in applying electricity to 

 the body, and that the skin should be soaked for twenty-five 

 minutes previously. Mr. Carpenter also exhibited a "chain- 

 band" of Mr. Pulvermacher, and a small voltameter by the 

 same inventor, in which the liberated gases force some of the 

 water up a irraduated tube as a gauge of the current. The 

 author drew attention to the necessity of seeing that the skin 

 should be dry in handling some electric light machines, else dis- 

 agreeable sh' rcks might result. Prof. Ayrton believed that the 

 danger of elecric lighting currents lay rather in their discon- 

 tinuity than their electromotive force. The Brush currents, 

 which have proved fatal, are more discontinuous than those of 

 the Gramme machine, &c. Adverting to the presence of elec- 

 tricity in the air as influencing health, he suggested that the 



