NA TURE 



Wov. 25, 1880] 



aV, he tried this with perfect success in Uruguay ; he supposes 

 tlmt curiosity was the motive. A large coral upon the copper 

 of a man-of-war, Capt. King states, is not unprecedented ; he 

 remembers in 1839 seeing one of the size and shape of a large 

 caulitlower, taken from the bottom of a vessel of the Indian 

 navy, in the Persian Gulf, by a pearl-diver. 



Prof. Graham Cell has promised to read a paper before 

 the Society of Arts upon his "Photophone " at the ordinary 

 meeting on Wednesday, December I. As considerable interest 

 is likely to attach to this paper it is announced that only members 

 of the Society can be admitted, and that they will be required 

 to provide themselves with special tickets i-sucd for the 

 occasion. 



We referred in the "Physical Notes" of our issue of 

 November 1 1 to a paper read before the American Association 

 at Boston by Prof. Young, \vhich combated certain phenomena 

 in thermo electricity which were alleged to have been observed 

 by Herr Exner. We have since received from Mr. T. Brown of 

 Belfast a letter in which, on behalf of Prof. Franz Exner of 

 Vienna, he expressly disavows any such discoveries as those 

 which Prof. Young has set himself to refute. We readily accord 

 to our courteous correspondent the opportunity for this dis- 

 avowal, since any reflections cast even inadvertently upon the 

 accuracy of Prof. Franz Exner's work might unfairly prejudice 

 readers against the general reliability of the researches which he 

 has published in another department of science, and which our 

 readers are aware are just now exciting considerable attention. 



In Nature, vol. xxii. p. 616, it was stated, on the authority 

 of the Japanese papers, that Prof. Atkinson had, "during a 

 sojourn in the Mitake Mountains of the Province of Koshu, dis- 

 covered another valuable deposit of coal." We are now informed 

 that although Mr. Atkinson visited the Mitake Mountains last 

 summer, he can lay no claim to so important a discovery. 



The Hon. Sir Ashley Eden, K.C.S.I., has appointed Babu 

 Ambika Churn Sen, M.A., and Synd Sakhawat Ilossein, B.A., 

 a native of Behar, to the two scholarships of 200/. a year each, 

 recently created by the Bengal Government to be held at the 

 Royal Agiicultural College, Cirencester. 



The Procureur-General of Paris having sent an explanatory 

 note stating that he did not mean to attack the character of the 

 medical advisers of the public prosecutor, but merely to give 

 vent to his peculiar views, these gentlemen have withdrawn their 

 resignations and resumed their work. 



The Cutlers' Company have arranged for a course of lectures 

 being delivered, or papers read, at the hall of the company 

 during the ensuing winter season. The course will consist of 

 four lectures or papers upon subjects intimately connected with 

 the materials used in the manufacture of cutlery, the lectures to 

 take place on the following dates : — Wednesday, December i, 

 1880; Wednesday, January 5, 1881 ; Wednesday, February 2, 

 18S1 ; Wednesday, March 2, 1S81. Sir Henry Bessemer, C.E., 

 F.R.S., has promised to commence the course, and will, on 

 December i, read a paper "On the Manufacture and Uses of 

 Steel, with special reference to its employment for Edge Tools." 

 The admission will be entirely free, but by ticket, which may 

 be obtained on application to the hon. secretary, addressed to 

 the Cutlers' Hall. 



It is announced that the electric cable manufacturing firm, 

 Berthoud Borel and Co. of Cortaillod, in Neuchatel, have made 

 a highly important discovery in practical telegraphy. After a 

 long and expensive series of experiments they have succeeded in 

 devising a method of laying cables whereby the inductions of the 

 electric current from one wire to another, although the wires are 

 in juxtaposition, is prevented. This discovery, it is asserted, 

 removes the last obstacle in the way of the widest possible 

 extension of facilities for telephonic communication. 



85 



OUR ASTRONOMICAL COLUMN 



isThe Third Comet of 1S69. — This comet, the orbit of which 

 has so close a resemblance] to that of the comet discovered by 

 Mr. Swift on October 11, was detected at Marseilles by M. 

 Tempel on November 27, 1869, in the constellation Pegasus, 

 and appears to have been last observed on December 31 at 

 Leipsic and Kremsmunster, the hope of seeing it after the next 

 period of moonlight not having been verified. On November 29 

 Dr. Vogel, observing at Leipsic, described it as a very faint 

 large object elongated in the direction of the declination circle : 

 in the comet-seeker its diameter was about 6'. On December 7 

 it was still very faint, large, and elongated in the direction 300°, 

 the central condensation very slight. On the following night its 

 diameter was 5'; it had "a peculiar milky appearance" and 

 hardly .-my central condensation, so that observations were 

 attended with difficulty. On the 21st it was seen only v.ith 

 much exertion of the eye, but on the 31st, though the comet 

 was very faint. Prof. Bruhns considered his separate comparisons 

 certain to about ten seconds of arc. At Kremsmunster Prof. 

 Strasser found it " extr.iordinarily faint " during its entire visi 

 bility, and in consequence of wanting central condensation, very 

 difficult to observe, and hence considered that his positions would 

 not possess the ordinary degree of accuracy. The elements of 

 the orbit were calculated by Tiele, Oppolzer, Schulhof, and 

 Bruhns, the parabolic orbit published by the latter in No. 17SS 

 of the Astromvitische Nachiichlen being founded upon nearly 

 the whole extent of observation ; he remarks with respect to 

 it:— "Eine angestellte Vergleichung hiesigen Beobachtungen 

 scheint aber doch auf eine Abweichung der Bahn von der Para- 

 bel hinzudeuten . . ." We are not aware that any further 

 examination of this point was made. If the period of revolution 

 be really something less than eleven years, the circumstance of 

 the comet havingescaped observation prior to 1869 will not 

 nevertheless occasion surprise, considering that both in 1869 

 and 18S0 it has approached near the earth and has yet been 

 very faint and diffused, so that when the perihelion passage has 

 occurred at other seasons of the year it might be beyond reach 

 of the telescope. It will be most essential for the theory of the 

 comet's motion that observations should be continued as long as 

 possible at the present appearance, that if it prove to be one of 

 short periol its next return to perihelion may be closely pre- 

 dicted : the computation of the planetary perturbations during 

 the period 1869-S0 will of course be a necessary process with 

 this object in view. 



The Star Lalaijde 1013-4.— Mr. G. Knott has examined 

 this star, to which we lately drew attention, as being credited 

 with the very discordant magnitudes 5, 77, and 10. He writes 

 from Cuckfield on November 21 : "I looked the star up on 

 November S and again on November ig, and found it on each 

 occasion 7^9 mag., and sensibly equal to B.D. -H 51°, No. 131, 

 which forms a convenient comparison star. This estimate, it 

 will be seen, agrees nearly with that in the Diirchmitsterun^ ; 

 Harding marks the star 6m. 



CHEMICAL NOTES 



In the last number of the Bcrichte of the German Chemical 

 Society Herr v. Lippmann describes experiments which thow 

 that a solution of pure cane sugar, when charged with carbon 

 dioxide, is slowly converted into inverted sugar. If the carbon 

 dioxide be pumped into the sugar solution under pressure, the 

 rate of inversion is considerably increased : at 100° the inversion 

 takes place rapidly. 



In the Annalcs Chim. d Phys. the results of M. Raout's 

 experiments on the freezing points of alcoholic hquids are 

 detailed. An aqueous solution of alcohol containing I "6 per 

 cent, by volume freezes at - 0-5 ; a solution containing 47-9 per 

 cent, freeze? at - 32'. The freezing point of solutions containing 

 from 24 to 51 gram alcohol per 100 grm. water is decreased by 

 o°-52S for each gram of alcohol: when more than 51 grm. 

 alcohol are present to 100 grm. water no regular decrease inthe 

 freezing point was observable. The freezing points of various 

 wines are given in the paper referred to. 



In Comptcs rend. M. Kessler announces that he has prepared a 

 crystallised hydrate of hydrofluosilicic acid, viz., H.^SiFg. 2H„0. 

 The hydrate is a hard, colourless, very deliquescent solid, which 

 fumes strongly in air, and melts at about 19'. 



