410 Proceedings of the Tioyal Scoftish Socle fi/ of j4rt's. 



lOM January 1842. — Sir John Robison, K.H., President, in 

 the Chair. 



An Answer was read from the Secretary of State for the 

 Home Department, to the Society's Address to her Majesty 

 the Queen on the birth of the Prince of Wales, stating that 

 lier Majesty had been pleased to receive the same very gra- 

 ciously. 



An Answer was also read from G. E. Anson, Esq. Treasurer 

 to his Royal Highness Prince Albert, to the Society's Address 

 to his Royal Highness. 



The following Communications were then made : — 



1. A Model of an Apparatus for Tilting or Emptying Waggons at the 

 termination of Railways was exhibited and described by James Thomson , 

 Esq., Civil Engineer, Glasgow, F.R.S.S.A. — Thanks voted, and referred to 

 a committee ; and Mr Thomson was requested to furnish a written descrip- 

 tion, with a diagram, for the Society's Transactions. (840.) 



2. On the use of Chlorine for ascertaining the illuminating power of 

 Coal-Gas ; and on the comparative expense of Light derived from different 

 sources. By Andrew Eyfe, M.D., F.R.S.E., and F.R.S.S.A. The Bude 

 Light and some others were shewn. — Thanks voted, and abstract to be printed 

 in the Transactions. (846.) 



The author first alluded to experiments made some yeai-s ago, in which 

 lie proposed Chlorine as a means of ascertaining the illuminating power of 

 Coal- Gas, and he again adverted to the subject, owing to his having been 

 lately engaged in an enquiry as to the comparative illuminating power of 

 gases derived from different sources. In these trials, in addition to the usual 

 test, by the shadow, he had again recourse to the action of chlorine, and in 

 all his experiments he found the results to agree so nearly, that he conceives 

 that chlorine may be employed with the most implicit confidence for indicat- 

 ing the illuminating power ; which may he stated to be just as the amount 

 of condensation. He afterwards related the results of trials made with the 

 view of finding the comparative expense of light derived from other sources, 

 — a§ from a variety of candles made of tallow, wax, and other substances, 

 and also from oils, consumed both in common lamps and in others with con- 

 trivances adapted to them for the more perfect combustion of the oil. In 

 all of these, he found the light from gas by far the cheapest. Next came 

 the Solar lamp, and Naphtha, then the oils in Argand lamps, and lastly the 

 candles, of which the tallow were the least expensive, the wax and sper- 

 maceti the most so. He also stated tiiat the comparative expense of these 

 would depend on the quality of the gas, which varies much in different parts 

 of the Kingdom, and hence the value of the chlorine test, by which the illu- 

 minating power of different gases could be easily ascertained. 



3. On a method of softening the tone of the Clarionet for chamber prac- 

 lire. By Mr William Meikle, Town-end, Strath aven. Muted clarionets, 



