CHAP. VII. STEPHENSON'S SECOND SAFETY-LAMP. 115 



tunately none of the experimenters were injured by the 

 explosion. 



Stephenson followed up those experiments by others 

 of a similar kind, with the view of ascertaining whether 

 ordinary flame would pass through tubes of a small 

 diameter, and with this object he filed off the bar- 

 rels of several small keys. Placing these together, 

 he held them perpendicularly over a strong flame, and 

 ascertained that it did not pass upward. This was a 

 further proof to him of the soundness of the principle 

 he was pursuing. 



In order to correct the defect of his first lamp, 

 he accordingly resolved to alter it so as to admit 

 the air to the flame by several tubes of reduced dia- 

 meter, instead of by a single tube. He inferred that a 

 sufficient quantity of air would thus be introduced into 

 the lamp for the purposes of combustion, whilst the 

 smallness of the apertures would still prevent the explo- 

 sion passing downwards, at the same time that the 

 "burnt air" (the cause, in his opinion, of the lamp 

 going out) would be more effectually dislodged. He 

 accordingly took the lamp to the shop of Mr. Matthews, 

 a tinman in Newcastle, and had it altered so that the 

 air was admitted by three small tubes inserted in the 

 bottom of the lamp, the openings of which were placed 

 on the outside of the burner, instead of having (as in 



Mr. Turner's conduct towards George ' tionise by his inventions and improve- 



Stephenson was all the more worthy ments the internal communications 



of admiration, because at that time of the civilised world. The circum- 



the object of his friendly instruction ' stance is encouraging to those who, 



and counsel occupied but the position ! like Mr. Turner, are still daily devo- 



of a comparatively obscure work- ! ting themselves with equal disinte- 



man, of no means or influence, who j restedness to the education of the 



had become known to him only working classes in our schools and 



through his anxious desire for infor- mechanics' institutes. Though the 



mation on scientific subjects. He opportunity of lending a helping hand 



could little have dreamt that the ; to such men as George Stephenson 



object of his almost fatherly attention may but rarely occur, the labours of 



would achieve a reputation so distin- | such teachers are never without the 



guished as that which he afterwards most valuable results, 

 obtained, and that he would revolu- 



i 2 



