206 
DR. H. T. BARNES ON THE CAPACITY FOR HEAT OF WATER 
In fitting the copper cylinders into place, they were each wound with a small 
rubber tube, shown in section, in fig. 9. Through these rubber tubes on the two 
cylinders small copper wires were placed, and soldered to the ends near the heating- 
wire. These copper wires served both as potential terminals as well as a method of 
holding the rubber tubes in place on the copper cylinders. The rubber tube served 
three purposes; the holding of the cylinders central and firm, the stirring of the 
water as it flowed around the thermometer bulbs, and the insulation of the potential 
leads. 
The platinum heating-wire was fused at one end to a copper wire of the same size, 
which was in turn soldered with pure tin into the hole in the end of cylinder B, 
fig. 10. The other end of the heating-wire was soldered with tin directly to three 
copper wires, which served to draw the platinum wire into place in the fine-bore 
tube. 
When cylinder B, which was placed in the outflow end of the calorimeter, was 
shoved down into place as far as it would go, the heating-wire was about 3 centims. 
shorter than the fine tube at the further or inflow end. The three copper wires, 
which were attached to the heating-wire and protruded from the calorimeter tube, 
were pushed through slits cut for them between the copper screw and nut (shown in 
fig. 10) on cylinder A. These three wires could be drawn through readily with the 
screw only partly in place, and in this way by pulling the wires through, cylinder A 
was shoved down the calorimeter tube into its place in the inflow tube. When in 
place a screw-driver was inserted, and a jack to hold the cylinder from turning, and 
the copper screw turned into place. When it reached the part of the thread where 
the slits ended, the three wires were firmly gripped between the thread and screw. 
The copper screw was smoothed on the end so as not to cut through the wires, but 
simply to jamb them against the screw thread. When sufficiently firm a specially 
constructed cutter was introduced, and the wires cut off just at the head of the 
copper screw, this left the cylinder firmly attached to the heating-wire by the three 
copper wires. The glass-tubes for the differential thermometers were placed in the 
two ends of the calorimeter, and slid into the two cylinders prepared for them. The 
tubes were put in empty, as it was found better to introduce the thermometers 
themselves after the calorimeter was fitted up and in place in the water-jacket. The 
ends of the calorimeter were closed watertight by means of a rubber stopper placed 
on each glass thermometer tube near the end of the calorimeter tube. The eight- 
copper wires at the ends were placed in slits prepared for them in the rubber stoppers 
together with the two rubber tubes containing the potential terminals. Bubber 
cement was then placed over the surface and allowed to dry. A strip of rubber 
sheet, also covered with rubber cement, was placed so as to surround each rubber 
stopper and a portion of the end of the calorimeter, and on being cemented together 
formed a sleeve. This rubber sleeve was then firmly wired in place around the rubber 
stopper and wires, and also around the calorimeter tube. The ingress for the water 
