56 



NA TURE 



[May 17, 1900 



ment has a Cooke photo-visual lens of 4 inches aperture 

 and 16 feet focal length, the primary image being used 

 on plates 12 x 12 inches. 



In addition, the De la Rue coronograph (4f inches 

 aperture and 72 inches focal length), Graham coronograph 

 (3 inches aperture, 21 inches focal length), and Dallmeyer 

 coronograph (6-inch aperture rapid rectilinear, 48 inches 

 focal length) will be used. Parties of the volunteers will be 

 engaged in one or other of the following observations : — 



Disc drawings of corona ... about 19 volunteers. 



Observations of ring spectra 5 ,, 



Observations with pocket slit 



spectroscopes... ... ... ,, 4 ,, 



Observationsof shadow bands... ,, 6 ,, 



Observations of stars and 

 other celestial objects visible 

 during totality ... ... ,, 20 ,, 



Shadow phenomena, both 



atmospheric and terrestrial ... „ 6 ,, 



Colours of landscape, &c. ... ,, 12 ,, 



Meteorology, temperature, 



pressure, &c. ... ... ... ,, 15 ,, 



Photographs of landscape ... ,, 5 ,, 



Natural history effects on men 

 and animals ... ... ... ,, 3 ,, 



In addition to these instruments, several of the ob- 

 servers will obtain photographs of the eclipse spectra by 

 means of diffraction gratings and prisms fixed in front of 

 their own small cameras. Those with gratings are likely 

 to be specially useful, as the dispersion is sufficiently 

 great to render it possible for the bright line spectra to 

 show up from the continuous spectrum, and there is the 

 further advantage of the large field given by an ordinary 

 rectilinear, so that the spectrum of the streamers may 

 also be obtained. 



Prof. Copeland, Astronomer Royal of Scotland, will 

 also occupy a station at Santa Pola, using a telescope of 

 40 feet focus. 



The British Astronomical Association and the French 

 Astronomical Society will each send parties to both 

 Alicante and Algiers. As, however, the former place 

 is so well occupied by Sir Norman Lockyer's party, the 

 third official party from the British Government will 

 occupy a station at Algiers, and will consist of Prof. 

 Turner, Mr. Newall, Mr. Evershed and Mr. Wesley. 



Prof. Turner will photograph the corona with one of 

 the double cameras used in previous eclipses, one of 

 which is arranged to polarise the coronal light before it 

 reaches the photographic plate, and thereby determine 

 the extent to which this light is initially polarised. In 

 addition, he also hopes to repeat his work of 1893 and 

 1898 for determining photometrically the relative bright- 

 ness of the corona at varying distances from the limb. 



Mr. Newall will have three instruments under his 

 charge, viz. : — (i) A four-prism slit spectrograph for ob- 

 taining the spectrum of the "flash," and of the corona. 

 In the latter he hopes to obtain material for showing the 

 difference, if any, between the spectrum of the coronal 

 rays and the other portions. (2) An objective grating 

 camera for photographing the spectrum of the corona 

 in monochromatic light. (3) A polariscopic camera for 

 photographing the corona, special attention being de- 

 voted to the study of any differences between the darker 

 and brighter rifts. 



Mr. Wesley, the assistant secretary of the Royal 

 Astronomical Society, has for many years critically 

 studied the minute structure of the corona, he being the 

 draughtsman who has engraved the reproductions of 

 many of the corona photographs of past eclipses for 

 publication, but has not hitherto had an opportunity of 

 studying it from nature. By the kindness of M. Tre'pied, 

 the Director of "the French Governinent Observatory at 

 Algiers, Mr. Wesley will be enabled to examine the 

 corona with the powerful "equatorial coude" (about 

 8 inches aperture). 



NO. 1594, VOL. 62] 



Mr. Evershed will not be stationed at Algiers itself, 

 but intends to observe from a place near the limiting 

 line of totality, about twenty miles south of Algiers, so 

 that he may photograph the " flash " spectrum with 

 somewhat longer exposure than near the central line. 



Mr. and Mrs. Maunder will repeat at Algiers their 

 programme so successfully carried out at Buxar, India, 

 in 1898, but with larger apparatus. This will include 

 short exposure photographs of the inner corona, and 

 others with long exposure for extensions and streamers. 



Mr. and Mrs. Crommelin will go to Algiers, and take 

 photographs of the corona and of the shadow as projected 

 on the atmosphere. 



It is alsostated that Mr. Percival Lowell, of Arizona, 

 and Prof. Todd, of Amherst College Observatory, U.S.A., 

 will occupy stations near Tripoli, in North Africa. It is 

 to be hoped that favourable weather will enable the latter 

 astronomer to successfully use his electrical control, by 

 means of which he has arranged that a great number of 

 photographic cameras shall be automatically exposed for 

 varying times, all of which are operated from one re- 

 volving drum with delicately fitted electrical contacts. 



The eclipse occurs at the European stations about 

 4.0 p.m. Greenwich time, so that it may be possible to 

 communicate the results of the various expeditions to 

 the evening papers of the same day. 



Mention should be made of the generous arrange- 

 ments which have been made by the authorities of all 

 the Governments concerned, whereby the usual customs 

 tariff and examination will be dispensed with, provided 

 the observer is furnished with a certificate showing that 

 his baggage is really for eclipse observation. The rail- 

 way companies in Spain have also consented to convey 

 passengers at half the usual fares. 



Charles P. Butler. 



THE ROYAL SOCIETY SELECTED 

 CANDIDA TES. 



FIFTEEN candidates were selected by the Council of 

 the Royal Society on Thursday last for election 

 into the Society. The following are the names and 

 qualifications of the new Fellows : — 



George James Burch, 



M.A. (Oxon). Lecturer at the University Extension College, 

 Reading. Author of the following papers : — (i) " Experiments 

 on Flame" (Nature, 1885-86); (2) "A Perspective Micro- 

 scope" {Proc. Roy. Soc, vol. xiii. ) ; (3) "Researches on the 

 Capillary Electrometer" {Proc. Roy. Soc, vol. xlviii., ibid., 

 vol. lix., Phil. Trans., vol. clxxxiii(A)., The Electrician, July, 

 1896). "On a Method of drawing Hyperbolas" {Phil. Mag., 

 Jan., 1896). Also joint author of the following papers : — (i) 

 "Dissociation of Amine Vapours" (with Mr. J. E. Marsh) 

 (/oiirn. Chetn. Soc, 1889) ; (2) " E. M.F. of certain cells contain- 

 ing Nitric Acid" (with Mr. V. H. Veley) {Phil. Trans), vol. 

 clxxxii(A). ; (3) "Effect of Injury in Muscle" (with Prof. 

 Burdon-Sanderson) {Proc. Physiol. Soc, 1893) 5 (4) "Action 

 of Concentrated Acids on Metals in contact" (with Mr. S. W. 

 Dodgson) (/'wf. Chein. Soc, 1894); (5) " D'Arsonval Physical 

 Theory" (with Mr. L. E. Hill) {fourn. Physiol, 1894); (6) 

 "The Electromotive Properties of Malapterwus elcclriciis'" 

 (with Prof. Gotch) {Phil. Trans., 1896). 



Supplementary Certificate. 

 Author of the following scientific papers in addition to those 

 stated in the first certificate: — "On Prof. Hermann's 

 Theory of the Capillary Electrometer " {Proc Roy. Soc, vol. Ix., 

 p. 328); "The Tangent Lens-gauge" {Phil. Mag., 1897, 

 p. 256) ; "An Inductor- Alternator for Physiological Experi- 

 ments " {fotirn. of Physiology, vol. xxi., 1897 ; "An Account 

 of Certain Phenomena of Colour Vision with Intermittent 

 Light" {ibid.) ; " Artificial Colour Blindness, with an Examina- 

 tion of the Colour-Sensations of 109 Persons" {Phil. Trans., 

 vol. clxli., 1899) ; joint author with Prof. Gotch, F.R.S., of the 

 following scientific papers : — "The Electrical Response of 



