Proceedings of the Soclett/ of Arts, 407 



session, the day of meeting be changed from Wednesday to 

 Monday, at the usual hour, keeping clear, as at present, of the 

 days on which the Royal Society hold their meetings." 



3. On the motion of Mr Dunn, curator of the Museum, it 

 was resolved unanimously, '* That a committee be appointed 

 to inquire and report, whether the present arrangement for 

 bringing out its printed Transactions should be continued, or 

 whether some other arrangement should be substituted." — 

 Committee appointed. 



4. The list of prizes to be offered by the Society for session 

 1840-41, as altered according to the resolutions of last meeting, 

 was submitted in proof, and, after some alterations, was adopted, 

 and ordered to be printed and advertised as usual.* 



13M Mai/ 1840. — First Extraordinary Meeting for this Ses- 

 sion. Sir John Graham Daly ell, President in the Chair. 

 The following Communications were made : — 



1. On tlic comparative Heating Po^er of cUfTerent kinds of Gas-burners 

 used for Illumination ; and on the best means of burninn^ Gas as a source 

 of Heat. By Andrew Fyfe, M.D., F.R.S.E., M.S.A. (707.)— In a pre- 

 vious paper Dr Fyfe stated, as tlie results of his experiments on the illu- 

 minating power of different kinds of gtis-burners, that, for equal con- 

 sumpts of gasj the light given by jets being considered as 100, that by 

 fish-tails is as about 140, by bat-wings as about IGO, by argands, so con- 

 structed that as the flame must form one continued ring, about 180. 

 From the numerous experiments on tlic comparative heating power of 

 the same burners, he found that the heat evolved was in proportion, not 

 to the light which they afford, but to the quantity of gas consumed, and 

 that the same is also the case where the gas is burned on wire gauze, 

 a practice now generally followed where gas is used as a source .of 

 heat. Accordingly, when gas is to be used for this purpose, it is of no 

 consequence, in so far as the evolution of heat is concerned, in what 

 manner the gas is burned, provided the combustion be complete, and 

 provided means be adopted for preventing as much as possible the loss 

 of heat. With regard to expense, Dr Fyfe stated that he had been able 

 to evaporate one gallon of water by the combustion of from sixteen to 

 eighteen feet of gas, which, at the rate gas is sold in Edinburgh, would cost 

 twopence, or nearly so. Were coal employed for this purpose the expense 

 would not exceed about the fourth of a farthing. Though gas is much 

 more expensive than coal, yet where expense is not an object, it may be 

 used advantageously, as in some processes of cooking. When the gas is 

 burned on a gauze of about three inches in diameter, the expense of the 

 gas on each gauze will vary from one halfpenny to a pennj' per hour, ac- 



* Vide p. 412. 



