March lo, 1881J 



NATURE 



441 



there v\ere excavated the other day some vases of Egyptian 

 manufacture, which will greatly interest archfficlogists. They 

 are made of a particular kind of paste, composed of white clay 

 and glafs, and are extremely brittle. All round they have high 

 relief representations of the animals worshipped by the ancient 

 Egyptians. 



A PHONOGRAPH of a new construction will be tried in the New 

 Polyglot Institute of Paris, for the purpose of teaching pupils 

 the art of pronouncing correctly the difficult words of foreign 

 languages. 



A SCHOOL for clockmaUers has been organised in Paris, and 

 was inaugurated yesterday by a meeting at the Conservatoire 

 des Arts et Metiers. 



The new part of the Transactions of the Asiatic Society of 

 Japan contains a paper by Dr. Edkins on the influence of 

 Chinese dialects on the Japanese pronunciation of the Chinese 

 part of the Japanese language. 



We have received part 3 of the Transactions of the Epping 

 Forest Club, containing the address of the president, Mr. 

 Meldola, proceedings, and list of members. 



We have to acknowledge the receipt of a postal order for 

 2s. 6d. from " Bullphumpus" for the John Duncan Fund. 



The additions to the Zoological Society's Gardens during the 

 past week include an Indian Leopard (Fclis pardtts) from India, 

 presented by the Duke of Buckingham and Chandos ; an Entellus 

 Monkey (Scmnopithecits ciilclhis) from India, a Greater Sulphur- 

 crested Cockatoo (Cacatiia galerita) from Australia, a Blue- 

 fronted Amazon {Chrysotis /estiva) from Brazil, deposited ; four 

 Indian Kat Snakes (Ptyas mucosa) from India, a Matamata 

 Terrapin (C/telys matamata) from Upper Amazons, purchased; 

 two Calandra Larks (ALIanvcoryplia ca/andra), European, a 

 Chinese Quail (Coturni.r c/iinensis) from China, two Fire-tailed 

 Finches (Erythrtira prasina) from Java, received from Paris. 



OUR ASTRONOMICAL COLUMN 

 The Solar Parallax. — M, F.aye has just communicated to 

 the Academy of .Sciences a ] aper on the actual state cf our 

 knowledge of the sun's parallax, of which we subjoin some par- 

 ticulars, wiihout professing to regard his mean result as neces- 

 sarily so deP-iiitive as he appears to view it himself. 



M. Faye considers that there is no other scientific constant, the 

 determination of which depends on an equal number of results 

 completely independent of one another, and obtained by methods 

 so totally different, and subdivides ihe various values assigned for 

 the sun's mean parallax as follows ; — 



8*85 by Mars (Cassini's method) ... Newcomb. 

 Geometrical 879 by Venus, 1769 (Halley's method) Powalky. 

 methods, 88l by Venu-, 1874 ,, ,, Tupman. 



8"-82 I 8-87 by Flora (Galle's method) Galle. 



879 by Juno ,, ,, Lindsay. 



("S'Sl by the lunar inequality (Laplace's 

 method) 



"^ahmir' ^ ^'*5 ^y '^* monthly equation of the 



S"'Si ' 1 earth Leverrier. 



^ 8'83 by the perturbations of Venus and 



I. Mars Leverrier. 



Phvsical f 8799 Velocity of light (Fizeau's me- 



U 1 I thod) Coniu. 



"g,,.g, ' I 8-813 Velocity of light (Foucault's 



1^ method) Michelson. 



With regard to the first value by " mechanical methods," M. 

 Faye mentions that he has obtained it by adopting for the co- 

 efficient of the inequality I25"'2, the mean between the results 

 of Sir George Airy from the Greenwich observations, and that 

 of Prof. Newcomb, from Ihe observations made at Washington, 

 taking for the moon's mean parallax, 57' 2"7, and for her mass 



I 

 a^g." Leverrier found the value S"'9S from the said equa- 

 tion, which was reduced after correction by Mr. Stone for 



two small errors to 8"*8s. The value from the perturbations of 

 Venus and Mars assigned by Leverrier was 8"'86, but one of the 

 numbers requiring a small correction, it is reduced to 8""83. 

 Michelson, after bringing to bear upon Foucault's method im- 

 provements wbicli M. Faye s.ays completely su-'mounted all 

 difficulties, found for the velocity of light 299940 km., while 

 Helmert altered Cornu's result to 299990 km. With Struve's 

 constant of aberration the corresponding values for the solar 

 parallax are 8"799 and S"'8i3, as above. 



The general mean in which it may be considered that the 

 errors of the individual results, ibtained by so many methods, 

 are to a great extent compensated is 8"'S2, and to this value M. 

 Faye, for reasons given, attributes a probable error of ± o""Ol6, 

 The me.in value by the physical methods is 8" 806, and by 

 astronomical methods 8"'825. He then considers which of these 

 values is the more reliable, and states that he does not hesitate 

 in giving the preference to the physical result, and arrives at the 

 conclusions : — 



1. That the method of the physicists is superior to all others, 

 and cught to be substituted. 



2. That the value of solar parallax, 8"'8i3 (by physical 

 methods), is now determined to about ^^ of a second. 



3. That the seven astronomical methods of procedure cor. verge 

 more and more towards that value, and tend to confirm it without 

 equalling it in precision. 



M. Faye adds that he has no idea of attempting to diminish 

 the importance of the observation of tha approaching tran-it of 

 Venus : but as Leverrier pointed out, " 11 faut que les efforts 

 des astronomes aient pour but d'obtenir une precision toute nou- 

 velle dans leur prochaines expeditions." Without neglecting 

 the contacts, he considers it will be desirable to employ to a 

 greater extent than was done in 1S74 "les precedes si puissants 

 de la photographic," to which, be it observed, M. Faye from 

 his own experiences drew attention a quarter of a century back. 

 He thinks it will be very surprising if that admirable method of 

 procedure, which has already succeeded so well in measuring 

 delicate stellar groups, should fail for the transit of Venus, or 

 under circumstances more favourable for its ajiplication. 'The 

 value S"'8i3 for the sun's parallax, which appears to him defini- 

 tive, is in accordance with that adopted by Laplace in the 

 Micanique celeste, 27^2 centesimal seconds or 8" •812. 



Swift's Comet, 18S0 e. — Mr. Winslow Upton of the Naval 

 Observatory at VVashington, sends us elements of this comet, 

 which, as he remarks, afford a further confirmation of the 

 5i-years' period already assumed. He employed two ob'-erva- 

 tions made with the meridian circle of the VVashington Obser- 

 vatory on October 25 and November 23, and one with the 

 26-inch equatorial on December 22. The elements are as 

 follow : — 



Epoch 18S0, October 25-5 M.T. at Washington. 



Mean anomaly 



Perihelion from node ... 

 Ascending node .. 



Inclination 



Angle of eccentricity ... 



Log. semi-axis major ... 



The corresponding period is 21S 



; M. Eq. 



357 48 49 '3 



io6 18 13-8 j 



296 41 55-4 



5 31 3'S 1 



42 31 39'7 



0-518438 



days, or a little less than six 



years. The middle place is represented within the small errors 

 of - I "-2 in longitude and — o"-6 in latitude. 



PHYSICAL NOTES 

 Mr. T. C. Mendenhall of Japan has measured with a so- 

 called "invariable pendulum" the acceleration of gravity at 

 the top of the extinct volcano Fujiyama, which plays so promi- 

 nent a part in the mythology and in the art of Japan. The value 

 found for the summit of the mountain was^ = 9-7886, whereas 

 at Tokio the value was found to be 9-7984. The average baro- 

 metric pressure at the summit was 19-5 inches, the mountain 

 itself being an almost perfectly symmetrical cone of vertical 

 angle 138°, and of a height of 2-35 miles. It rises alone out of 

 a plain of considerable extent, and appears to be composed of a 

 uniform rock of porous nature. Tradition states that the moun- 

 t<ain was thrown up in a single night in the year n.c. 2S6. The 

 density of the rock in the lump was 1-75, but when reduced to 

 powder the density was 2-5 ; competent geologists conclude the 

 mean density of the mountain mass to be 2-12. Assuming the 

 mountain to be a cone of semi-vertical angle of 69", and density 

 2-12, Mr. Mendenhall calculated its attraction upon a particle 



