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LXXXII. Description of an Appendage to Torrr’s Blowpipe; 
to make it serve as a Substitute for Bruoxss’s Gas Blow- 
pipe. by Mr. H. B. Lexson, 
To Dr. Tilloch. 
Vottingham, Nov. 16, 1821. 
Sir, — Tux great danger attendant upon the burning the ex- 
plosive mixture of oxygen and hydrogen in Brookes’s Gas Blow- 
pipe (even with Cutnming’s Safety Cylinder) has for some time 
been a source of regret to the votaries of science. ‘Those who 
have witnessed the beautiful and brilliant effects produced by the 
gas blowpipe, and have considered the interesting nature of the 
facts that have been thereby developed, and the probable im- 
portance of the result of future experiments, must lament that 
any one should be debarred from using that powerful agent. 
The interposition of a screen may indeed prevent the fatal effects 
attending the explosion of the gases; but when the operator 
hears the alarming crash that announces the destruction of his 
apparatus, he must experience considerable disappointment at 
the loss of his blowpipe, and the disagreeable interruption of his 
experiments. ‘The screen itself is an inconvenience, as it confines 
the operator to one particular spot, and requires much compli- 
cated apparatus, in order to allow the condensing syringe to be 
worked by a person on the outside of the screen. A desire to 
obviate these inconveniences led me some time since to contrive 
the safety appendages of which I now send youa description, as 
adapted to the improved hydraulic blowpipe described in No. 6, 
New Series of the “ Annals of Philosophy.” ABCD, fig. 1 (PI. VI. ) 
represent the body of the blowpipe, which should be about twenty 
inches long, six inches wide, and two feet deep, and may be made 
of tinned iron, well painted or japanned both inside and outside. 
There should he a lid to open on hinges at A, with a small hole 
in it to allow the top of the safety cistern to pass through it; 
this lid is not represented in the figure. The box is separated 
into two parts as represented by the dotted lines at BD; the 
lower part of the box is about eleven inches deep, and communi- 
cates with the upper part by the cylinder E: this cylinder is si- 
tuated in the centre of the division B D; it is three inches in di- 
ameter, and reaches within half an inch of the bottom of the 
box. The air chamber F is supplied with gas or air through 
the pipe G, which should be about two feet long, one-fourth of 
an inch in diameter, and should be placed half an inch from the 
bottom of the box. The air issues through the pipe H, which 
should be about eleven inches long and the same diameter as the 
pipe G. To the top of the pipe H (which is strengthened by 
passing through the small shelf 1) the safety appendages aie 
Vol, 58, No, 284. Dec, 1821, 3 E screwed. 
