108 DESCRIPTION OF A LAMP. 



Defer iption of a Lamp upon Aiigand's Principle, with Im- 

 provements, in which the Oil is maintained at the fame Level by 

 the conftant Aclion of a Pump. By Citizens Car c el and 

 Careau *. 



Excellence of JLiAMPS with a double current of air are among the inven- 



gand. amP ° f * t ' 0ns °^ tne c 'g^teenth century, which are molt honourable to 

 the induflry of France, and of which the general ufe fufficiently 

 befpeaks the value. But it is not enough that a great light 

 fliould be produced without fmell or fmoke, but an objed of 

 nearly equal utility confifls in producing the light fteadily, 

 with economy, in the moil advantageous form, and bell adapt- 

 ed to economical purpofes. 



Improved by Citizens Carcel and Careau have fucceeded in this object. 



£53? and Ca " We mal1 not dwel1 u P on the obflacles they muft have met 

 with in arriving at the degree of perfection they have obtain- 

 ed ; it will be fufficient to fhew the value of their invention, 

 if we can prove that it furpaffes every thing of the kind which 

 has yet been exhibited. This lamp has the double advantage 

 of exhibiting all the good qualities of the lamp we hefore pof- 

 feffed, without their inconveniences. The nozle undergoes no 

 alteration by heat, neither is the wick deilroyed, but almoft 

 conflantly preferves its whitenefs. 



Inconveniences The oil in ordinary lamps is liable to flow out by its expan-. 



otiamps of the { 10n wnen heated ; but in this mechanical lamp it conflantly 

 ufual conftruc- _ _ *, T 



tion. prelerves its level. By difpeniing with the relervoirs of oil 



in thofe lamps which are called fountain lamps, thefe inventors 

 have fucceeded in affording light which is not fliaded on any 

 fide. In this refpect the lamp is very economical, becaufe 

 nearly half the light of a fountain lamp mufl neceflarily be in-. 

 tercepted by the receiver, which requires to be placed above 

 the level. But in thefe the refervoir is in the foot, which ren- 

 ders them more portable ; and from this circumflance, as well 

 as the other advantages of their conflruction, there is no dan- 



* From Les Annales des Arts & Manufactures, vi. 269. I am 

 much obliged to my correfpondent C. D. for directing my atten-* 

 tion to this article, 





ger 



