68 Dy. Hare’s Improved Eudiomeiers. 
having proved insecure, a new and unobjectionable mention 
has been advpied. 
A Fig. 1. 
WW. 
In the instrument represented re the preceding cut, the 
igniting wire is soldered into the summits of the two brass 
wires (WW), which pass through the bottom of the socket 
(5). parallel to the axis of the glass recipient (G), within which 
they are seen. One of the wires is soldered to the socket, 
the other is fastened by means of a collar of leathers, packed 
by a screw, so that it has no metallic communication ‘with the 
other wire, unless through the filament of platina, by which 
they are visibly connected sags and which | have already 
called the igniting wire. The glass has a capillary orifice at 
the apex (A), which by means of a lever and spring (appa- 
rent in the drawing) 1s closed, unless when the pressure of 
the spring is counteracted by one of the fingers of the ope- 
rator. The sliding rod (seen at R) is eccursiely graduated 
10 about 320 degrees 
So easy is it to wonbpulite with this instrument, that any 
number of experiments may be performed in as many min- 
utes, The ignition of the platina wire, is caused by either of 
four calorimotors, each consisting of four plates of zinc, and 
of five of copper. They are all suspended te one beam, as as 
my he seen in fig. 2. following. 
