284 BI-OW PIPE, 



V. 



Description of a Portable Blow Pipe for Chemical Expc^ 

 riments. Bj/ W. II. Wollastox, M.D. Sec. R.S. S)C. 



To Mr. Nicholson. 

 Sir, 



Pocket blow JL HE consideration of those instruments which facili- 



**'** ' tatc thfe attainment of chemical knowledge cannot ba 



thought foreign to the design of a Journal which pro#^ 



fesses to have for one of its objects the diflfusion ofche- 



nitcal information ; I am in hopes, therefore, that a short 



description of a portable pocket blow pipe may be accept- 



^ able to many of your readers. 



T t 1 I'd It consists of three parts, so adapted to each other that 



and draw out, they may either be packed together, one within the other, 



*"^' as in Fig. 1. PL VIII. which represents them of their 



actual size, or they may be connected for use, as in Fig. 2. 



^ in which the whole is reduced to one half of its real 



dimensions. 



In Fig. 1. the interior tube is sKcwn to be longer than 

 the exterior ; and it is made so, that it may be more rea- 

 dily withdrawn. 



In each figure, the upper edge of the large end appears 

 turned outward, in order to diminish the elfort of the lips 

 requisite for retaining it in the mouth. 



In Fig. 2. it will be seen that the small extremity is 

 placed obliquely (at an angle of about 120°), with the de- 

 sign tliat the llame impelled by it may be carried to a 

 more convenient distance from the eye, so as to answer 

 the purpose of a longer blow pipe. 



This oblique piece is itself composed of three parts, of 

 which the largest is made stronger than the rest of tha 

 blow pipt^j that it may not be strained by frequent use. 

 One end of this is closed, and into the other is inserted a 

 small peg of wood, perforated so as to receive the tip, 

 / which is intended to be occasionally separated, for tha 

 purpose of passing a fine needle into it to remove any 

 accidenta^obstruction. 



TliO 



