February 17, 1898 J 



NA TURE 



379 



headquarters of scientific associations. Here the Chemical 

 Society offered us a most kindly and cordial welcome, and 

 provided us with a meeting-place which is not only more 

 generally accessible than the old one, but is also on other 

 grounds more convenient to most of our Fellows. 



By this tinie the general affairs of the Society had assumed a 

 more business-like condition. Amongst other things, greater 

 care was exercised with regard to the acceptance of communi- 

 cations. I need hardly say that no paper is in these days 

 allowed to be read unless it has been first referred to some 

 competent authority and favourably reported on. The most 

 distinguished physicists in the kingdom have given their services 

 as referees, and our heartiest thanks are due to them for the 

 care and patience which they have ungrudgingly bestowed upon 

 a somewhat ungrateful task. 



The practice was also introduced of putting the more im- 

 portant papers into type before they were read, and distributing 

 proofs among such of the Fellows as were known to be specially 

 interested in the subjects to which they related. This course 

 has led to a considerable improvement in the value of the 

 discussions. 



The most recent step in advance consists in the adoption of a 

 scheme for greatly extending the list of journals from which the 

 monthly abstracts are made. Hitherto the papers abstracted 

 have been exclusively such as had been published in foreign 

 journals, and were ot primarily scientific interest. In the pre- 

 sent year, as the result of an agreement with the Institution of 

 Electrical Engineers, the number of the abstracts is to be 

 largely increased, British publications and papers of a technical 

 character being included in their scope. The arrangement in 

 question is open to the objection that it entails the loss of our 

 monopoly in the publication, for members of the Institution of 

 Electrical Engineers will, like ourselves, receive copies of the 

 abstracts, and will share with us whatever credit attaches to 

 their production. The objection, however, appears to be in 

 the main only a sentimental one, and of small weight in relation 

 to the substantial advantage accruing to our members — an 

 advantage which could not possibly have been provided out of 

 our own unaided resources. [Reference was then made to the 

 advantages afforded by the Physical and other kindred Societies 

 in promoting friendly intercourse among fellow- workers in a 

 particular branch of science.] 



Through the kindness oi certain influential gentlemen be- 

 longing to the Society, we have from time to time been afforded 

 the opportunity of holding a meeting in some well-known 

 physical laboratory either in town or in the country. I myself 

 have had the privilege of taking part in most agreeable pil- 

 grimages to Oxford, Cambridge and Bristol, and have also 

 been among those who enjoyed the hospitality of Profs. Adams, 

 Carey Foster, Ayrton and Thompson at their laboratories in 

 London. I have pleasure in announcing that the Council has 

 accepted an invitation from our Fellow, Mr. Porter, to go to 

 Eton for the next meeting on February 26, and I trust that our 

 appreciation of his kindness will be testified by a large gather- 

 ing. It is a little difficult to beg for favours, but I may be 

 allowed to suggest to those who are in a position to exercise 

 similar hospitality, that they have it in their power to contribute, 

 in a material degree, and in more than a merely scientific sense, 

 to the well-being of the Society. 



[The second part of the address dealt with the discovery of 

 the Zeeman effect ; some of the principal papers published by 

 the Physical Society in 1897 ; the appointment of the National 

 Physical Laboratory Committee, and the foundation of the 

 Rbntgen Society.] 



THE INSTITUTION OF MECHANICAL 

 ENGINEERS. 



'T'HE annual general meeting of the Institution of 

 ^ Mechanical Engineers was held in the theatre of the 

 Institution of Civil Engineers on the evenings of the loth and 

 nth insts. The usual formal proceedings having been gone 

 through, the retiring President — Mr. E. Windsor Richards — 

 introduced the new President, Mr. Samuel W. Johnson, who is 

 locomotive superintendent to the Midland Railway. There 

 were two papers down for discussion, and there was also an 

 adjourned discussion on a paper entitled " Mechanical Features 

 of Electric Traction," which had been read and partially dis- 

 cussed at the last meeting of the Institution. This paper wa.s 



contributed by Mr. Philip Dawson, who is largely interested in 

 the introduction of mechanical appliances in connection with 

 electrical engineering into this country from America. Under 

 these circumstances it was natural that the contribution should 

 be of a general rather than a scientific character. The prominent 

 feature in the paper was the fact that electrical traction has 

 spread so rapidly in America, whilst very little has been done 

 in this country. For instance, out of a total of nearly i5,ox) 

 miles of tramways in America in the year 1895, 12,583 miles are 

 worked electrically. Cable traction, which was at one time so 

 popular, and which seemed to have so promising a future before 

 it, has been quite eclipsed by electrical methods, there being 

 only 600 miles of rope tramway in the States in the same 

 year. Steam has even a lower total, there being but 519 

 miles. Horse traction supplies the balance of something over 

 1200 miles. Great Britain and the Colonies in the year 1896 had 

 but 167 miles of electric tramway, thus being far below Germany, 

 which had a total of 618 miles. The only other European 

 country having more than 100 miles was Austro- Hungary, with 

 a total of 120 miles. Belgium had 90 miles, France 67, Italy 

 50, and Switzerland and Russia 30 miles each ; whilst other 

 European countries contribute 30 miles altogether. ' 



It is not necessary we should follow the author in the 

 practical details he gives regarding the various features of 

 motors, trucks, cars, permanent way, conductors, methods 

 of transmission, generating stations, &c. The long discus- 

 sion on this paper resolved itself very l.irgely into a contro- 

 versy as to whether English engineers should follow American 

 precedents. Prof. Unwin, in the speech that he made, entered 

 a timely protest against the spirit of detraction which animated 

 a good many of the speakers. As he said, American engineers 

 may not be perfect in all their practice, and it is quite possible 

 improvements may be made upon their methods, still they have 

 had considerable experience, and what they have done repre- 

 sents actual work, whilst in this country we have practically 

 no precedents in regard to electrical tramway practice. 



The only paper read at the meeting was a contribution by 

 Prof. Frederic W. Burstall ; it embodied the first report of the 

 Gas Engine Research Committee that had been appointed by 

 the Institution, and of which Prof. Alexander Kennedy is the 

 chairman. The object of the experiments described was to de- 

 termine the effect produced on the economy of gas engines by 

 altering one or more of the conditions which govern their work- 

 ing. The problem is one of a complex nature and presents con- 

 siderable difficulties, especially as the gas engine has not like 

 the steam engine been made the object of investigation by many 

 authorities for a great number of years. The factors con- 

 sidered by the Committee were the amount of cornpression, 

 the speed, the ratio of air to gas, and the amount of 

 heat rejected through the walls of the cylinder. The 

 engine used was of small size, perhaps too small to afford 

 altogether satisfactory results ; but the Committee were not 

 to blame for this, for they had to work with such tools as they 

 could command . The nominal power of the engine was 2 N. H. P. , 

 and the maximum that could be developed was 5 I. H. P ; it was 

 made by Messrs. Fielding and Piatt, of Gloucester. The author 

 stated that an increase of compression in a gas engine is often 

 regarded as being conducive to more economical results, but 

 it is uncertain whether the increase in economy is really due 

 to the compression alone. It is, perhaps, fair to state that the 

 Committee recognised that the absolute economy of the engine 

 tried — which was specially constructed for experimental pur- 

 poses — would be inferior to the economy that could be obtained 

 by a larger motor ; still, it was concluded that the comparative 

 economies under different conditions would not be different in 

 the t%vo sizes ; moreover, it was stated that it would have been 

 impossible to measure with precision certain quantities, such as 

 the volume of air, had the engine been larger. The compression 

 employed in the expertments varied between 35 lbs. and 90 lbs. 

 per square inch. The observations taken included measure- 

 ments of the gas and of the air supplies, measurement of heat 

 rejected into the jacket, sampling ot exhaust gases, and deter- 

 mination of the I.H.P. developed. Seventeen tests were taken, 

 and the mechanical efficiency of the engine was found to vary 

 from 76 to 84 f)er cent. , the mean value of the whole seventeen 

 tests being 81 per cent. On a full power test the engine was run- 

 ning at 197 revolutions per minute, the compression per square 

 inch absolute was 103 lbs., the ratio of clearance to cylinder 

 volume was 025, and the ratio of explosions to the maximum 

 possible was 92 per cent. Under these circunastances the 



NO. 1477, VOL. 57] 



