I JO 



NA ruRt 



[May 31, 1900 



so extensive that several years must elapse before the work is 

 completed. There will be seven volumes in all, having the 

 following subjects and editors :— Arithmetic and algebra, Prof. 

 W. F. Meyer ; analysis, Prof. II. Burkhardt ; geometry, Prof. 

 Meyer ; mechanics, Prof. F. Klein ; physics. Prof. A. Sommer- 

 feld ; geodesy and geophysics. Prof. E. Wiechert ; astronomy 

 (under arrangement) ; history, philosophy, and didactic 

 questions, Prof. Meyer. The work is published under the 

 auspices of the Munich and Vienna Academies of Science, and 

 the Gottingen Society of Sciences, and no mathematical library 

 will be complete without it. 



Sir John Lubbock's book on " The Scenery of Switzerland, 

 and the causes to which it is due " has been translated into 

 Italian by Dr. L. Scotti, and is published by Signor U. Hoepli, 

 of Milan, as " Le Bellezze della Svizzera, Descrizione del 

 Paesaggio e sue Cause geologiche." The first English edition 

 was noticed in Nature of September 10, 1896 (vol. liv. 

 P> 439) ; the translation is from the third edition, published 

 in 1898. 



The use of acetylene for lighting rooms upon a commercial 

 scale renders its purification from sulphuretted and phosphuretted 

 hydrogen imperative, on account of the injurious effects of the 

 products of combustion of these impurities in a confined space. 

 Numerous substances have been put forward by different inven- 

 tors as effecting the desired purification, among which may be 

 mentioned ferric chloride, chromium sulphate, petroleum, benz- 

 ene, chromic acid, bleaching powder, and cuprous chloride. 

 "The ideal purifier should remove the impurities as completely 

 as possible, should not absorb acetylene itself, and should not 

 -communicate any objectionable properties to the purified gas. 

 The current number of the Moniteur Scientifiqiie contains ab- 

 stracts of numerous papers upon this subject. From these it 

 would appear that solutions of metallic salts do not wholly 

 remove the impurities, chromic acid and chloride of lime solu- 

 tions being the only substances that effect a complete puri- 

 fication, and of these the former is preferable, as with the latter 

 explosions have occurred, probably owing to the formation of 

 chloro-acetylene. 



The additions to the Zoological Society's Gardens during the 

 past week include a Diana Monkey {Cenopitkecus diana) from 

 West Africa, a Common Squirrel {Sciunis vulgaris), British, 

 presented by Mrs. Morris ; a Common Paradoxure ( Para- 

 doxurus tiiger) from Java, presented by Mr. E. E. Hewens ; a 

 Boddaerl's Snake [Drymobius boddaerli), a Chequered Elaps 

 {Elaps leiniiiicatus), a Rat-tailed Opossum {Didelphys nudi- 

 caudata) from Trinidad, presented by Mr. Leon Bernstein ; a 

 Summer Snake {Contia oestiva), a Mexican Snake {Coluber 

 melanoleucus), six Menobranches {Nicturus maculalus), five 

 American Green Frogs {Rana halecina) from North America, 

 deposited. 



OUR ASTRONOMICAL COLUMN. 

 Astronomical Occurrences in June. 

 June 2. 8h. 33m. to 9h. 35m. Moon occults k Cancri (mag. 

 5-0). 

 4. 9h. 49m. to loh. 45m. Transit of Jupiter's Satellite 



III. (Ganymede). 

 7. 9h. 58m. to loh. SSm. Moon occults the star 

 D.M. - 10°, 3570 (mag. 60). 



11. 8h. Jupiter in conjunction with moon. Jupiter 



1° 29' North. 

 II.' iih. 23m. to I2h. 43m. Transit of Jupiter's Satellite 

 III. (Ganymede). 



12. Partial eclipse of the moon. 



I3h. i6'2m. First contact with penumbra. 

 I5h. 24*2m. First contact with shadow. 

 I5h. 27 -Sm. Middle of the eclipse. 

 I5h. 3i'om. Last contact with the shadow. 



NO. 1596, VOL. 62] 



June 12. I7h. 39'om. Last contact with the penumbra. 



It will be a very small eclipse, the proportion of 

 the moon's surface covered by the earth's shadow 

 being equal to only one-thousandth part. The fainter 

 outlying shadow will, however, cover a large region, 

 but will be only faintly discernible. 



13. 7h. Mercury in conjunction wtih e Geminorum. 

 Mercury, o' 3' South. 



13. 9h. 40m. to loh. 52m. Moon occults the planet 

 Saturn. 



15. Venus. Illuminated portion of disc, 0'i44. Mars, 



0962. 



16. 8h. 48m. Jupiter's Satellite IV. (Callisto) in con- 



junction south of planet. 

 19. Saturn. Polar semi-diameter, i7"'o. Outer minor 



axis of outer ring, i8"'87. 

 23. 5h. Saturn in opposition to sun. 

 Search Ephemeris for Eros. — The following is continued 

 from the ephemeris by J. B. Westhaver {Astronomical Journal, 

 No. 479, vol. XX. p. 185). 



Ephemeris for 12/1. Greenwich Mean Time. 



1900. R.A. Decl. Mag. 



h. m. s. ^ , ,1 



June 2 ... 23 57 26 ... -f4 22 22 ... 



4 ... o 36-1 ... 4 57 6 ... 12-9 



6 ... 4 87 ■•• 5 31 57 - 



8 ... 7 407 ... 6 6 57 ... 12-9 



10 ... II 119 ... 6 42 6 ... 



12 ... 14 42*5 ... 7 17 24 ... 12-8 



14 ... 18 12-4 ... 7 52 51 ... 



16 ... 21 417 ... 8 28 27 ... 127 



18 ... 25 10-3 ... 9 4 12 ... 



20 ... 28 38-1 ... 9 40 5 ... 127 



22 ... 32 5*3 ... 10 16 8 ... 



24 ... 35 31-8 ... ID 52 19 ... 12-6 



26 ... 38 57-5 ... II 28 39 ... 



28 ... 42 22-4 ... 12 5 8 ... 12-5 



30 ... 45 46-6 ... 12 41 47 ... 



July2 ... 49 lo-o ... 13 18 34 ... 12 5 



Prof. Howe is reported to have discovered the planet in the 

 constellation Aries. 



Oxford University Observatory. — In the twenty-fifth 

 annual report of the Savilian professor at Oxford, Prof H. H. 

 Turner briefly reviews the history of the institution. The late 

 Prof. Pritchard, ia 1873, successfully appealed to the University 

 for facilities to institute the means of carrying on astronomical 

 research, but the plans originally projected being modified by 

 the presentation of Dr. De la Rue's instruments, the building 

 was not finished until 1875. However, notwithstanding his 

 advanced age. Prof. Pritchard carried out before his death two 

 important researches, the Uranometria Nova Oxoniensis, and 

 the determination of stellar parallaxes ; and initiated a third, the 

 share of the Observatory in the International Astrographic Chart. 

 During the six years of Prof. Turner's directorship the 

 energies of the Observatory have been chiefly directed to 

 carrying out, as expeditiously and economically as is consistent 

 with the necessary accuracy, this great work of fundamental 

 astronomy. One or two more years will be required to com- 

 plete it, but the work is at present as well advanced as at any 

 of the other eighteen observatories which are collaborating. 

 In addition, the Observatory has been utilised as an educa- 

 tional institution for the benefit of the students of the University. 

 For the Astrographic Catalogue, 736 plates are now measured, 

 and 705 completely reduced, out of the 1180 falling to the share 

 of the Observatory. Measurements have been made on a plate 

 supplied by Prof. E. C. Pickering to determine the optical 

 distortion of a photographic doublet. A preliminary discussion 

 of these measures indicates a distortion varying as the cube of 

 the distance from the centre of the plate ; this somewhat sur- 

 prising result, if confirmed, will enable the reduction of photo- 

 graphs of star fields of wide angle to be made with great 

 accuracy. 



RousDON Observatory, Devon.— Sir C. E. Peek sends us 

 another of his pamphlets (No. 6), containing the detailed par- 

 ticulars of the observations of variable stars during the past 

 decade. The observations of T Cassiopeia extend over the 

 ten years 1889-1898, and those of R Cassiopeite from 1887- 

 1898. At the end of the observation the light curves of the two 

 stars are shown. 



