July 2, 1896] 



NA TURE 



207 



curves of variable stars of the Algol type. S. Antlia; has 

 usually been regarded as belonging to this class, and is specially 

 interesting on account of its short period of 7h. 46"8m. , and 

 because it is said to retain its full brightness for less than half its 

 period, this last peculiarity being opposed to the probability of 

 the rariation being due to a darU eclipsing body. On construct- 

 ing a curve from a series of 177 measures, the conclusion is that 

 S. Antli.e is not a star of the Algol type, but its light is 

 constantly changing, and that it should rather be classed among 

 the variables of the S Cephei or ij Aquiire type. An interesting 

 feature of the light curve for this star is that the increase of 

 light is slower than the diminution. As this ratio (o"62) in most 

 other short-period variables is from 0'20 to 033, there seems 

 reason for dividing the two classes. 



The star /3 Lyr;E is commonly regarded as a variable of 

 short period of the same class as the above. " Observations of 

 its spectrum, however, show that two or more bodies, revolving 

 round each other, are present. The light curve found by 

 .Argelander may be closely represented by assuming that the 

 primary minimum is caused by the eclipse of the brighter body 

 by the fainter, and the secondary minimum by a similar eclipse 

 of the fainter body by the brighter. This star should therefore 

 be taken from the class of ordinary short-period variables and 

 included among the stars of the Algol type." Lockyer finds, 

 however, that there is evidence of greater complication in the 

 system ; and the theory of eclipses alone fails to account satis- 

 factorily for the velocities in the line of sight which are obtained 

 from the measurements of photographs of the spectrum of the 

 star. 



AWARD AND PRESENTATION OF THE 

 RUM FORD PREMIUM. 

 T N conformity with the terms of the gift of Benjamin, Count 

 Rumford, granting a certain fund to the American 

 Academy of Arts and Sciences, the Academy is empowered to 

 make, at any annual meeting, an award of a gold and silver 

 medal, being together of the intrinsic value of three hundred 

 dollars, as a premium to the author of any important discovery 

 or useful improvement in light or in heat, which shall have been 

 made and published by printing, or in any way made known to 

 the public in any part of the continent of America, or any 

 of the American islands ; preference being always given to such 

 rliscoveries as shall, in the opinion of the Academy, tend most 

 to promote the good of mankind. 



At the annual meeting of 1885, the Academy awarded the 

 Kumford premium to Thomas Alva Edison for his investigations 

 in electric lighting, and the presentation of the medals took place 

 at the meeting of May 13, 1896. 



\'ice- President Goodale, in presenting the medals, made the 

 following remarks : — 



" It would be highly presumptuous for one whose knowledge 

 of physics is of the most elementary character to occupy the 

 time of the Academy by any statement of his own in conveying 

 these medals. Happily such a course is unnecessary. The 

 Chairman of the Kumford Committee has placed at our command 

 a brief statement which makes clear the ground of the award. 



" 'The Rumford Committee voted, June 22, 1893, t^*' it 's 

 desirable t(j award the Rumford medal to Thomas Alva Edison 

 in recognition of his investigations in the field of electric light- 

 ing, and they confirmed this vote on October 9, 1S93, •" 'he 

 following words : " Voted for the second time to recommend to 

 the Academy that the Rumford medal be awarded to Thomas 

 Alva Edison for his investigations in electric lighting." 



" The Committee reached the conclusion expressed by these 

 votes after long deliberation and after careful sifting of all the 

 evidence which was at their disposal in regard to Mr. Edison's 

 claim for priority in the construction of the incandescent lamp, 

 the conception of the central lighting station together with the 

 multitude of devices, such as the three-wire circuit, the dis- 

 position of the electric current feeders, and the necessary methods 

 for maintaining the electric potential constant. 



" The Committee felt that they could not decide upon Mr. 

 Edison's claim for priority in any particular invention in this 

 new industry. Indeed, Courts of Law, after prolonged litigation, 

 have found it difficult to decide how far Mr. Edison was in 

 advance of contemporary workers. The task given to the 

 Kumford Committee to decide who is most worthy of the Rum- 

 ford medal, especially in the field of the application of electricity 



NO. 1392, VOL. 54] 



for the production of light and heat, is not an easy one. The 

 number of investigators is now so large that it is no longer 

 possible, in general, for one man to claim to be the first to apply 

 electricity to a new field. The successful application is the 

 result of many minds working on the same problem. Although 

 the Committee did not feel justified in expressing the opinion that 

 Mr. Edison invented the incandescent carbon filament lamp, or 

 that he was the first to arrange such lamp in multiple on the 

 circuit, thus producing what is popularly termed a subdivision of 

 the electric light, or that the Edison dynamo had greater merits 

 than the machine of Gramme and Siemens and others ; still, 

 they are convinced that Mr. Edison gave a great impulse to the 

 new industry, and that he was the first to successfully instal a 

 central electric lighting plant with the multitude of practical 

 devices which are necessary. They believe that this impulse was 

 due to his indefatigable application, to his remarkable instinct in 

 whatever relates to the practical application of electric circuits, 

 and to his inventive genius. They, therefore, have unanimously 

 recommended to the Academy to bestow the Rumford medals 

 upon him, feeling that the work of Mr. Edison would especially 

 appeal to the great founder of the medals — Count Rumford — if he 

 were living. 



" The Academy has accepted the report of the Rumford Com- 

 mittee, and has voted to confer the gold and the silver medal 

 upon Mr. Edison. The recipient finds it impossible to be 

 present at this meeting of the Academy, and has requested Prof. 

 Trowbridge to act as his proxy and to receive the medals for 

 him. 



" In the name of the Academy, I beg you. Prof. Trowbridge, 

 to accept the charge of conveying these medals to Mr. Edison's 

 hands. It would be most ungracious for us who are assembled 

 in this room, which is flooded by this steady and brilliant electric 

 light, to withhold our personal thanks for what Mr. Edison's 

 investigations and practical activities have done for us all. And, 

 hence, I may venture to say that our thanks and all good wishes 

 are to be conveyed with the Rumford medals." 



Prof. Trowbridge replied as follows : — 



" Mr. President, and gentlemen of the Academy, I accept 

 the medals for Mr. Edison ; and at his request I wish to express 

 his deep sense of the great honour the Academy has conferred 

 upon him. His work in the field of electric lighting has been 

 the subject of prolonged litigation, and at times he has had 

 doubts, in reading the opinions of learned experts, whether his 

 work has been original, or whether he had really contributed 

 anything to the world's progress. The recognition of his labours 

 by the American Academy of Arts and Sciences, regarded by 

 Count Rumford in his gifts as the coequal of the Royal Society 

 of London, is, therefore, especially grateful to him. Acting as his 

 proxy, I thank the members of the Academy for the distinction 

 which they have, by their votes, conferred upon him." 



CAUSES OF DEATH IN COLLIERY 

 EXPLOSIONS. 



A REPORT, by Dr. John Haldane, on the causes of death in 

 ■^^ colliery explosions, with special reference to the Tylors- 

 town, Brancepeth, and Micklefield explosions, was published in a 

 Blue-book a few days ago. The report contains a vast amount of 

 valuable information on the composition of after-damp, the 

 action on men and lights of the gases present in, or mixed with, 

 after-damp, the action of after-damp, heat and violence, along 

 the track of an explosion, the distribution of after-damp and 

 other gases in a mine after an explosion, the distribution of 

 smoke in underground fires, the positions at which bodies are 

 found after an explosion, and the means of saving life in colliery 

 explosions and fires. To understand the dangers to life after a 

 colliery explosion, and the possibilities of escaping these dangers, 

 it is necessary to have a clear idea of the action, both on men and 

 lamps, of the gases which are likely to be present in the air of 

 the mine. These gases, so far as is known, are carbon dioxide, 

 carbon monoxide, nitrogen, firedamp, and sulphurous acid. 

 Oxygen may be deficient or absent. Dr. Haldane discusses the 

 efiects of these gases sfri'a/im, and the information he brings 

 together, as well as his own careful observations, should be 

 valued by colliery managers, while it will certainly interest 

 chemists and physiologists. 



In the case of the Tylorstown explosion, which. Dr. Haldane 

 says, was evidently propagated through the three pits by coal-dust, 

 fifty-seven men were killed. Of this number fifty-two, or 91 



