328 



NATURE 



\_August 5, 1880 



nebula was found on the following evening in R.A. 

 i8h. 4'3m. and Dec. -28° 12'. Both, but particularly the 

 first, are only minute, and can be with difficulty dis- 

 tinguished from stars, except by their spectra. The 

 discovery was not the result of accident but of a search 

 with a direct vision prism inserted between the objective 

 and eyepiece of the 15-inch telescope. A star appears as 

 a coloured line of light, while a planetary nebula forms a 

 bright point, and is recognised instantly in sweeping. 

 Many hundred or thousand stars can thus be examined 

 very rapidly, and a single nebula picked out from among 

 them. This method promises to add very greatly to the 

 list of known planetary nebula;, which now number about 

 fifty. Probably a systematic search for these objects 

 crossing a considerable part of the heavens will be made 

 at this Observatory. Our knowledge of that distribution 

 will thus be greatly increased, and we shall know that 

 their absence in certain parts of the sky is not due to an 

 ornission to look for them. Any planetary nebula as 

 bright as a twelfth-magnitude star would probably be 

 detected by the method proposed. Bright lines or other 

 peculiarities in the stellar spectra will also be looked for. 



Doubt has been thrown on many of the attempts to 

 measure the parallax of planetary nebula; owing to the 

 haziness of the borders of these bodies. The minuteness 

 of the disks of the nebula; noted above could permit their 

 positions to be determined with great precision, and 

 would thus show a very minute parallax. 



Cambridge, U.S., July 15 Edward C. Pickering 



NOTES 



An influential committee has been formed from among the 

 members in the Section of Zoology of the Paris Academy of 

 Sciences and others eminent in that department, to obtain 

 subscriptions for a medal in honour of M. Milne-Edwards, the 

 doyen of French zoologists. 



A MOVEMENT has been set on foot to obtain subscriptions to 

 a memorial fund in honour of the late Rev. J. Clifton Ward, 

 w hose name must be well known to our readers as a working 

 geologist who made valuable contributions to his science. Mr. 

 Ward, moreover, 'did great service in promoting a love of science 

 in Cumberland, and the Association for the Advancement of 

 Literature and Science, for which he did so much, has taken 

 the fund heartily "up. It ought to receive many subscrip- 

 tions outside of the Association, and we commend it to the 

 liberality of our readers. Subscriptions should be sent to 

 the Rev. Canon Eattersby, St. John'.s Parsonage, Keswick, and lo 

 Mr. Edwin Jackson, hon. treasurer, Keswick Library and Scien- 

 tific Society. It is proposed to expend the fund in the erection 

 of a mural tablet in the church of St. John, Keswick, and the 

 remainder in laying the foundation of a fund for the education 

 of Mr. Ward's two daughters. 



In answer to a question in the House of Commons as to the 

 cause of the delay in the removal of the Natural History Collection 

 from the British Museum to South Kensington, and when that 

 removal would be completed, Mr. Walpole said he believed the 

 delay had been caused by the facts that the building in which 

 the collection was to be placed was not handed over to the 

 Trustees of the British Museum until June, and that the grant 

 made by the Treasury was not sufficiently large to cover the 

 whole estimated expense for the cost of the removal. He believed 

 the removal of the mineralogical, geological, and botanical col- 

 lection would be completed by the end of the year or in the 

 spring of next year ; and that as far as the zoological collection 

 was concerned, its removal would depend very materially upon 

 the gr,ant which the Treasury might feel itself at liberty to make 

 for the purpose. 



Prof. Ed. Van Beneden is at present at Bergen for the pur- 

 pose of working out the embryonic development of tlie Lemming, 



which is likely to prove extremely interesting, because that of 

 the guinea-pig is so abnormal. 



A few months after Leverrier's death a commission was 

 established for determining the best means of protecting collieries 

 from firedamp. The Commission has written a very long report 

 recording the causes of 420 accidents. Sixty-four projects pre- 

 sented by private individuals have been examined, and some new 

 instruments have been de-igned and are being constructed, viz., 

 an anemometer by Vicaire, a manometer by Le Chatellier, and a 

 registering apparatus for the quantity of air introduced into the 

 g.illeries. But the composition of coal explosive dust has not 

 been determined, nor the extent of its influence on catastrophes ; 

 the chemical analysis of Grisau has not been completed, and the 

 salvage question has not been exhausted. The only .substantial 

 benefit is a compilation of mining regiUations and a series of 

 propositions which have been transmitted to the French Ministry, 

 and will be laid before Parhament next session. 



The detailed programme of the annual meeting of the Iron 

 and Steel Institute, to be held at Diisseldorf on August 25, 26, 

 27, and 28, is now published. The proceedings commence with 

 a concert at the Tonhalle on Tuesday evening, August 24. On 

 Wednesday there is to be in the morning a general meeting of 

 members at the Tonhalle, where the institute will be received by 

 the local authorities ; in the afternoon a visit to the exhibition 

 and to works near Diisseldorf; and in the evening the annual 

 dinner of the institute at the Tonhalle. On Thursday and 

 Friday there are to be general meetings in the morning for the 

 reading and discussion of papers ; the afternoons are to be 

 devoted to excursions by special trains to various iron and steel 

 works in the neighbourhood of Diisseldorf, followed by concerts 

 in the evenings. The whole will be brought to a close by a 

 Rhine excursion on Saturday, which is timed to bring members 

 by 10.30 p.m. to Cologne, vid Rolandseck, Bingen, and 

 Coblentz. The general secretary is Mr. J. S. Jeans, whose 

 address up till August ig is 7, Westminster Chambers, Victoria 

 Street ; and after that date, Tonhalle, Diisseldorf. 



The Aldini gold medal (worth 1,000 lire) will be awarded by 

 the Academy of Sciences of the Institute of Bologna to the best 

 memoir on galvanism (animal electricity). Memoirs to be 

 written in Italian, Latin, or French, and sent in before June 30, 

 1882. 



The Bencke prizes (first, 1,700 marks; second, 60 marks) of 

 the Philosophical Faculty of Gottingen University are offered 

 for investigation, theoretical and experimental, of diffraction 

 phenomena in the case of non-homocentric light sources, as, 

 especially, a circular and a square luminous surface of uniform 

 brightness of the emitted simple or compound white light. 

 Memoirs to] be written in German, Latin, French, or English, 

 and sent in before March ii, 18S3. 



A NEW process for obtaining stereotypes for printing has been 

 discovered by M. Emile Jeannin, a sculptor of Paris, who pro- 

 pof es to employ for that purpose the material known as celluloid. 

 The process of preparation takes only half an hour, when the 

 types are once set up, and the plates thus produced are remark- 

 ably suitable for working on cylinder machines running at a high 

 speed, being very light, flexible, and very durable. In this last 

 respect indeed they surpass metal plates, affording, it is said, 

 50,000 impressions, whereas even an electrotyped copper plate 

 backed with lead will only last for 30,000. 



The astronomical observatory established on the Trocadero, 

 is not the only scientific establishment which has found a home 

 in the palace of the last Universal Exhibition. A number of 

 microscopes have been arr.anged in a special room for the benefit 

 of public instruction. The instruments lent by M. Joubert 

 have been placed on the lop of one of the towers, where a lift 



