f52 Mr H. H. Blackadder on the Combustion of 



On the Combustion of Alcoholic Fluids, Oils, S^-c. in Lamps, with 

 observatiwis on the Colour and Constitution of Flame *, By 

 Henry Home Blackadder, Esq. F. R. S. E. Communi- 

 cated by the Author. 



1 . — Of Lamps xvithout Wicks. 



J\, POROUS or filamentous substance, that has the property of 

 raising fluids by capillary attraction, has hitherto been consider- 

 ed an essential part of a lamp for burning oils or alcoholic fluids ; 

 and this part of the lamp, termed the wick, has been made of 

 various vegetable and mineral substances, such as cotton, lint, 

 moss, asbestus, mica, small wires, &c. All combustible fluids, 

 however, that are commonly employed for producing light or 

 heat, may be burned with advantage in a lamp, without making 

 use of any wick. For this purpose, it is only requisite to have 

 a burner in the form of a tube, and made of a substance that is 

 incombustible, and a slow conductor of heat ; and, perhaps, it 

 would scarcely be anticipated how well glass and other slow con- 

 ductors are adapted for burners of this description, or how easily 

 such a lamp may be constructed. In their construction provi- 

 sion must be made for a constant supply of fluid to the burner, 

 without the influence of capillary attraction ; and this is effected 

 by having the burner so placed, as to be lower than the reser- 

 voir, the supply being regulated by a stop-cock or valve, or by 

 duly proportioning the size of the connecting tube. Lamps of 

 this description may be made of almost any form, and of almost 

 any solid material ; it being only essential, as already stated, 

 that the burner be a tube made of an incombustible and slow 

 conducting substance. For alcoholic fluids, the length of the 

 burner does not necessarily exceed an inch ; and for oils, it may 

 be reduced to the half or the fourth of that length. In Plate I. 

 Fig. 5. is represented a convenient and easily constructed lamp for 

 the combustion of alcoholic fluids. It consistsof a small glass globe, 



• The first part of this paper is an extract from a paper read before the Royal 

 Society, 1st May 1826. On that occasion, some of the facts noticed in the se- 

 cond pan were, cursorily adverted to. 



