198 THE SCIENTIFIC PAPERS OF 



could the human mind reproduce impressions imparted years ago 

 at will, or how could they be involuntarily revealed in our dreams? 

 The discoveries which are now brought before us will undoubtedly 

 serve to increase our stock of knowledge on physiological and me- 

 taphysical, as well as physical subjects, regarding molecular action, 

 of which we have hitherto had but very imperfect indications, and 

 I think we cannot be too thankful to those gentlemen who have 

 enabled us to discuss them as we have done, and I will therefore 

 move that a hearty vote of thanks be given to Mr. William Preece 

 for his communication. I think our thanks are also due to the 

 two discoverers who are here to-night, and have given us the 

 benefit of their views. I therefore propose that we also return 

 our thanks to Professor Hughes and Professor Graham Bell. 



In the discussion of tlie Paper 



" ON THE PRACTICAL APPLICATION OF ELECTRICITY 

 TO LIGHTING PURPOSES," by ME. JAMES N. SHOOLBEED, 



THE CHAIEMAN * (Dr. C. W. Siemens) said the electric light 

 was not a thing of yesterday. The first proposal to produce light 

 by electricity dated back to Sir Humphrey Davy and the beginning 

 of this century. Sir Humphrey Davy produced a very brilliant 

 arc with 3,000 Wollaston cells ; and shortly afterwards a still 

 larger arc was produced with 600 Bunsen cells. They were now 

 approaching the end of the century, and were still wondering 

 whether the electric light would be a success. The difficulty 

 which immediately presented itself was its great cost ; for to 

 maintain 600 Bunsen cells for a single light meant an expenditure 

 which put the light altogether out of the question for commercial 

 purposes. It was not until 1831 that a new ray of light was 

 thrown upon this question, through the brilliant discovery of 

 Professor Faraday. In that year he elicited an electric spark from 



* Excerpt Journal of the Society of Arts, Vol. XXVII. 1878-79, pp. 34, 35. 



