92 — of the Blowpipe of Hare and Brook. 
have, this season, ae of Mr. sachte 
blowpipe, and have a it with good success, to exhi 
homie of ies det this purpose, the two tubes 
which end in the frustrum of platina, are screwed out and 
inserted through a cork: they are then again screwed inte 
the platina, and are lastly connected with the tubes which 
ead to the omens: 4 gas, Sacks as when we are to use 
the compound blowp 
An apothecary’s F baat which should be frais éfieen to 
eighteen inches high, and of the capacity of about three or 
four gallons, is then filled with oxigen gas. This is easily 
done, without the air pump, by using a tube bent twice at 
right angles, and long enough to reach with one leg to the 
bottom of the bottle ; 3 the other leg is screwed to the stop 
cock of a large bell glass; this last is filled with oxigen gas, 
and by being pressed into the well of the pneumatic cistern, 
ee the long = of the bent tube i is passed to the bottom 
large bottle, on of the stop cock of 
the belt glass, the —— gas flows in, and lifts the common 
air out, and takes its place, thus filling the bottle with an’ at- 
pee oe ie 
mosphere 0 of oxigen gas, without resorting to the air pump, 
and without wetting the inside of the bottle, which would, 
of course, render the experiment nearly nugatory, and the 
result ambiguous. It is known when the bottle is filled with 
oxigen gas, by bringing a taper, that instant blown out, 
the 1 mouth of ‘the bottle, when if: full, the ve a2) will ber ( 
t 
ed. 
Things being, thus arranged, the flinse of the’tom 
blow ee is lighted, and is introduced into the Bottle, hea 
care not to bring it within nine or ten inches of the bottom : 
the cork which is.on the tubes, closes the mouth of the» 
bottle,* which is, from ee first moment, kept cold by 
copious streams of water poured i incessantly over the 
shoulders of the bottle, grb if neglected for a minute or - 
two, will grow hot—the vapour of the water formed will no 
r condense—it remains-in the condition of steam, and 
if the bottle be tight, will produce an explosion; or, if after 
the glass is once hot, we attempt to pour on water, the bot- 
Rss a But, ies Bh i ee ee is nO diffi: 
* Not, ie ver, absoluiely { ge fee of 
raccoon dre from the ly tg pees ‘rHlsion, oe. the great 
