77 



droops at a sound almost too faint for ordinary ears. And now I 

 have another point to introduce. 



Various substances have been produced from time to time as 

 sources of light. We may in fancy travel from the philosopher 

 of Laputa, mentioned l:)y Gulliver, who attempted to extract 

 sunbeams from cucumbers, and hermetically seal them up and 

 store them for future use, to such projects as laying a gas main 

 across the Atlantic, and thus bringing over our supply from a 

 natural source. I venture, however, to propose another substitue, 

 and more, I am quite willing to give the benefit to any person or 

 persons wishing to speculate. The substance I propose to burn, 

 is neither more nor less than ordinary atmospheric air. This is 

 certainly sufficiently plentiful and cheap enough to satisfy the 

 desires of the most economical. Nothing is easier than to cause 

 ordinary air to burn, provided we supply it with a suitable 

 atmosphere. Such an atmosphere is found in hydrogen or coal 

 gas. (Jet of air burned in coal gas ; description of apparatus). 

 This experiment is merely a reversal of the ordinary conditions, 

 and shows us that supposing our atmosphere consisted of coal- 

 gas or other combustible, air would then be the so-called 

 combustible body and coal -g is or what-not the supporter of 

 combustion. Heat and light in these cases are really but the 

 results of chemical action, and it matters not which substance is 

 present in greatest quantity, the action is the same. (As an 

 instance of brilliant combustion the time-honoured experiment of 

 burning phosphorus in oxygen may be introduced.) 



A few words more before conclusion. From the A'ery nature 

 of the subjects now treated, this discourse has necessarily been 

 abrupt and disjointed. Many phenomena have been referred to, 

 and time has not permitted their explanation. On behalf of the 

 institution I have the honour to represent, the Brighton School of 

 Science and Art, I wish respectfully to urge its claims upon you. 

 There is scarcely a trade or pi'ofession where knowledge of these 

 subjects is not an immense advantage, and in many an absolute 



