December 8, 1898] 



NA TURE 



135 



apparatus for experiments in voltaic electricity we notice a 

 useful school galvanometer, having several novel features, and 

 constructed in such a way that it can be entirely dismounted so 

 as to explain the method of construction before the students in a 

 class. Great care appears to be taken in the manufacture of 

 resistance coils, all of them being tested and adjusted to within 

 one-hundredth per cent, or one per cent, (according to price) of 

 their value. In the magnetic section an interesting instrument 

 described is Lenard's bismuth spiral for measurements of magnetic 

 fields. The principle upon which the instrument is based is 

 the change of resistance that occurs in bismuth when in a 

 magnetic field ; the alteration of resistance affording a means of 

 determining the number of lines of force in the field tested. 

 Many other instruments mentioned in the list show that Messrs. 

 Grifiin keep in touch with recent advances and educational 

 requirements. 



The Electrical Review for November 25 contains an 

 interesting account, with illustrations, of the electrolytic chlorate 

 works at St. Michel in Savoy. Power is supplied by the 

 river Arc, sixteen turbines, each keyed to a dynamo, being 

 employed. The solution of potassium chloride is placed in 

 insulated vats lined with lead, and having a capacity of 1 1 ,000 

 gallons. The anodes are of platinum-iridium, and the kathodes 

 of iron-nickel alloy. The primary electrolytic action is, of 

 course, the resolution of the potassium chloride into potassium 

 and chlorine; the potassium, however, forms potassium hydrate, 

 and liberates hydrogen at the kathode. The potassium hydrate 

 so formed is now brought under the influence of the chlorine 

 liberated at the anode ; and as a sufficient current density is 

 employed to keep the temperature above 45°, the action proceeds 

 according to the equation 6KOH + 3CI.J = KCIO3 -I- 5KCI + 3H3O. 

 The chlorate is easily separated from the more soluble chloride 

 by crystallisation. The works at .St. Michel, and another at 

 V'allorbes, are said to produce together 1800 tons of chlorate per 

 annum. The introduction of the electrolytic process has resulted 

 in a considerable fall in the price of chlorates. 



The additions to the Zoological Society's Gardens during; the 

 past week include a Mozambique Monkey {Cercopithccus pygery- 

 thnis) from East Africa, presented by Mr. A. D. Michael ; a 

 Mantell's Apteryx {Apteryx maiitelli) from New Zealand, pre- 

 sented by Sir Walter Duller, K.C.M.G., F.R.S. ; two Dwarf 

 Chameleons (Chamaeleon piimilus)itom South Africa, presented 

 respectively by Mrs. Todd and Mrs. C. Faraday Maypee ; a 

 Black Ape [Cynopilheciis niger) from the Celebes, an Osprey 

 Pandion haliaetus) captured at sea, a Praslin Parrot ( Coracopsis 

 barklyi) from Praslin Island, a Bell's Cinixys (Cinixys belliana) 

 from Tropical Africa ; a Home's Cinixys {Cinixys homeana) 

 from West Africa, three Painted Terrapins (Ckrysemys picla), a 

 Salt-water Terrapin {MalacocUmmys terrapin) from North 

 America, three Reeve's Terrapins (Damonia reez'esi), a. Black- 

 headed Terrapin (Damonia reevesi unicolor) from China, four 

 Caspian Terrapins (Clemmys caspica) from Western Asia, a 

 Japanese Terrapin {Clemmys japonica) from Japan, four European 

 Pond-Tortoises {Einys orbicularis), European, a Ceylonese Ter- 

 rapin (Nicoria trijuga) from India, two Blackish .Sternotheres 

 (Sternothaerus derbiamis) from Madagascar, a Spix's Platemys 

 {Platemys spixi) from Brazil, a Common Chameleon {Chamaeleon 

 vulgaris) from North Africa, two Rufescent Snakes {Leptodira 

 hotamboeia) from South Africa, deposited. 



OUR ASTRONOMICAL COLUMN. 



The New Comet Chase. — This comet seems to be bright- 

 ening, and is now in a good position for observation. It is moving 

 slowly towards the north-west, being situated now in the 

 southern part of the constellation of Leo Minor, roughly in a 

 prolongation of the^ line joining 71 and 7 Leonis. The Central- 



NO. I 5 19, VOL. 59] 



stelle sends us a circular (No. 15), which informs us of the 

 elements and a brief ephemeris computed by Coddington 

 from observations made on November 23, 24 and 25. Another 

 circular (No. 16), which has just come to hand, informs us of 

 more accurate elements and ephemeris which have been com- 

 puted by Herr. J. Miiller from two Harvard photographs taken 

 on November 14, and two Lick observations made on November 

 23 and 25. These are as follows : — 



T = 1S98 September 8-192 Berlin M.T. 

 a, = 358 43-83 ) 



n = 93 49-05 > 1898-0 



' = 21 35'35 ) 

 log'/ = 0-33144 



Ephemeris, Berlin Midnight. 

 1893. R.A. Decl. Br. 



8 ... 10 41 13 



10 ... 10 43 32 



12 ... 10 45 45 



14 ... 10 47 51 



-1-25 3-2 ... 1-4 



25 17-9 ... 1-4 



25 33-3 ... 1-4 



■f25 49-3 ... 1-4 



The Nebula ok Andromeda. — The variation in bright- 

 ness of a portion of the nebula of Andromeda, as announced by 

 Seraphimoff some weeks ago, does not seem to have been 

 generally corroborated, and the observations of Prof. Barnard 

 (Astrophysical Poitrnal for November) do not suggest any 

 variation. In June and July of the present year this observer 

 made a series of measures of the nucleus with reference to two 

 eleventh magnitude stars, one preceding and the other south, 

 and during this time the nucleus was well seen, though not 

 stellar. No trace of the Nova of 18S5, although carefully 

 looked for, could be observed. After Seraphimoff's an- 

 nouncement both the 40-inch and the 12-inch telescopes 

 were turned on to the nebula, but " it was evident that no 

 perceptible change had occurred in the nucleus or the nebula 

 itself . . . and the impression has always been that the nebula 

 is unchanged." 



Not only this observer, but both Hartwig at Bamberg and 

 Comas Sola at Catala {Astr. Nach. No. 3529), record no vari- 

 ation ; the former from eye observations and the lattet from 

 photographs taken before and after the announcement mentioned 

 above. 



The Planet Witt DQ. — In a previous number of Nature 

 (November 3) we brought together much of the information 

 that had been published concerning the interesting new planet 

 discovered by Witt. The importance of this small planet, which 

 at times approaches the sun nearer than Mars, necessitates that 

 it should be closely watched, and its motion accurately de- 

 termined. Needless to say, such observations are being carried 

 out in many observatories, so that when a sufficiently large part 

 of the orbit has been described we shall be presented with more 

 accurate elements. The elements previously published by 

 Berberich show now deviations from the true ones as gathered 

 from the observed and calculated positions of the planet. Mr. 

 H. N. Russell, of Princeton (the Astronomical Journal, Nos. 

 448-450), has formed some new normal places from a com- 

 parison of several observations, and the elements he has deduced 

 differ somewhat from those previously published. Millosevich, 

 in an interesting contribution to the Kcndiconti della R. 

 Accademia dei Lincei (vol. vii., series 5 a), has also computed 

 some new elements, so we give the following comparison : 



Epoch. 

 M 



log a 

 Period 



220 14 3-7 

 178 28 26-2 

 o 3 48 53-0 

 3" 6 57-1 

 13 13 3-8 



2010-131 

 0-164521 

 64s days. 



224 33 12-3 



175 47 5o'i|P 

 303 20 20-3>^ 

 10 45 I-Sj^ 

 12 55 13-6 



2003-86 



0-1654245 



i 646-75 days. 



222 23 28-7 

 170 I 20 S 



303 24 

 10 45 

 12 49 5-4 



2015-119 



0-163804 



644-06 days. 



20S \ 9 

 18-1 J ^ 



Prof. Simon Newcomb, in the same number of the Astro- 

 nomical fournal, refers to the future oppositions of this planet 



