116 Inproved Instrument for Venous Injection. 
cholera ; nor will this application be limited, it is conceived, .exclu- 
sively to this disease, but may become eventually a beneficial adju- 
vant in other diseases, which (resisting the ordinary methods of treat- 
ment) would otherwise be abandoned to the powers of the fell de- 
stroyer. 
Annexed is a plan of the apparatus proposed, which consists simply 
in the addition of a silver inserting tube and a glass air chamber to 
the “Improved domestic instrument of Maw,” (with which every | 
practitioner and private family is or ought to be supplied) or to the 
more complicated stomach and injecting pumps of Read and others. 
Method of use.—Adapt the whole as illustrated on the plate, then 
{the pump being placed in the liquor to be employed, the stopcock 
freely opened, and the tube inclined upwards) by a few strokes of 
the piston, the expulsion of all the air is thoroughly effected, as will 
be evinced to the operator by the uninterrupted, silent jet. Having, 
now the air-chamber nearly, and the remainder of the apparatus com- 
pletely filled with the liquid, close the stopcock so as to allow but a 
: guttatim’ emission, and insert with care the extremity of the tube into _ 
the vein previously prepared for its reception. 
The contained fluid being under compression and constantly flow- 
ing from the point of the instrument during its introduction, all admis- 
sion of air into the vessels is thereby effectually excluded. Another 
advantage arising from the stopcock, which should be noticed, is the 
perfect regulation of the current during the process of injecting. —~ 
TO THE EDITOR. 
PosTscRIPT. Providence, September 17, 1832. 
Sir—tIn a communication made to you for insertion in your Jour- 
nal on the 14th inst., I forgot to state, that I have occasionally tip- 
ped the points of the i inserting tube with a bulb (say half a line in 
diameter) which, from its exciting less irritation in the vein, I prefer 
to the oblique point as presented on the plate. 1 would also state 
that I have purposely omitted the metallic slide or guard to prevent 
the reflux of the liquor and flow of blood from the orifice, preferring 
rather the application of the finger of the operator for that purpose. 
