-TALLOW LAMP. 147 



low ran into ft, it would fink lower, and, in doing fo, move Defcription of a: 

 Ihe burner farther forward from the trough at the fame ^>"^6, ^^^J^'*^ urnuij 

 and lice vofUf and thus regulate the fupply fponlaneoufly : 

 But as it was neceflary that the pan (holding a fluid) (hould 

 always maintain an horizontal pofition during its movement, I 

 imagined this might be effeded by placing another arm be- 

 neath the balance-arm, and fixing a perpendicular piece, 

 fo jointed to the extremity of each as to move frefli and 

 fteadily, which piece fliould fupport an horizontal (land for 

 the pan. 



I had a lamp made in this manner, and found it anfwer my 

 intention perfedly. It required no attendance whatfoever, 

 but regulated its fupply with precifion ; and afforded, like- 

 wife, an agreeable fpedacle, having in its movements fome- 

 what the air oF thofe of an animal, from their exaiSt rela- 

 tion toxan evident object, and adopting themfelves to all its 

 changes. 



The lamp thus made atTumed the form in the figure, PI. IX. 

 where Treprefents the inclined trough for holding the tallow; P 

 ^- the pan for catching the tallow as it melted, and holding the 

 burner ; F the flame and burner j R the perpendicular piece 

 fufiaining a fupport for the pan ; B the balance moving freely 

 on its center in the ftand S, and jointed to R as before de- 

 scribed ; c the parallel arm ufed to keep R perpendicular, and 

 by its means horizontal ; id the counter weight, placed fo as 

 to move on the extremity of B by a fcrevv. The firfl frofiy 

 night fliewed me the neceffity of the addition of another part 

 to remedy an inconvenience I had not forefeen ; the dropping 

 tallow affuming the fcm of an ificle, joined the pan to tl.e 

 trough, and thus flopped its movement : As it was tfouble- 

 fome to break this oflT as it occurred, I contrived the follow- 

 ing means to prevent its formation : A little oblong fliding- 

 piece, the fame breadth as the trough, vyas placed clofe un- 

 derneath its lower part ; the extremity of this Aide was made 

 angular, that the melted tallow might fall from a fingle point; 

 a wire reprefented at L, moved it back or forwards as re- 

 quired : By this Aide the drop may be made to fall as clofe 

 to the flream of burning air from the flame as Is thought fit, 

 and all congelation prevented. 1 afterwards added a fort of 

 refledor to the lamp, which confiderably improved the light 

 not merely ading as its name implies, but alfo occafloning an 



L 2 incrtaf© 



