OF LIGHT AFFORDED BY CANDLES. - 43 



perpendicularly and (miffed, becaufe one part of a candle that 

 is fnuffed is thrown away, and another part flies off in the 

 form of fmoke. But this is not the only inconvenience that 

 attends the ufing of a candle in this manner, and which the 

 other method is free from, for the light which it gives is of a 

 bad quality, on account of its being variable and undulating. 



From the time that a candle is fnuffed till it wants muffing contrafted with 

 again, its ftrength of light fcarcely continues the fame for a ** e u FJgJt can- 

 Angle minute. But that variation which frequently takes place q^ltts (huffing, 

 in the height of the flame, is a matter of ftill more ferious 

 confequence. 



The flame of a long candle, when it burns fteadily, is about Extreme Hndu- 

 two inches high, but it very frequently rifes to the height of SSto^U* 

 four inches or upwards ; drops down again in a moment, till vertically i 

 it is lefs than three inches, and then rifes again. In this man- 

 ner the flame continues in motion for fome time before it re- 

 turns to its original dimenfions. But it does not continue long 

 in a quiefcent ftate before it begins a new feries of undula- 

 tions. In this manner the candle burns till the top of the 

 wick is feen near the apex of the flame, carrying off clouds of 

 fmoke. In this Hate of things the eye becomes uneafy for 

 want of light, and the fnuffers are applied to remove the in- 

 convenience. 



It is thefe fudden changes, and not the nature of candle and the mif- 

 light itfelf, that do fo much injury to the eye of the ftudent J^"'^" 

 and artift ; but that injury may be eafily prevented, by laying eyei. 

 afide the fnuffers, and in the place of one large candle, let 

 two fmall ones be ufed in the manner which I have before 

 taken the liberty to recommend. 



I remain, 

 SIR, 



Your's re fpect fully, 



EZEKIEL WALKER. 

 Lynn Regis, Dec. £0, 1802. 



Defcriplion 





