74 
MR. H. TOMLINSON ON THE INFLUENCE OF STRESS 
round which the wire was wrapped, and had taken the trouble several times to take off 
the cover and loosen the ice. I have now no doubt that the warmth of the hand in 
this last act had melted the ice sufficiently to allow the alteration of the melting- 
point temperature to be felt. 
Though these experiments were failures as far as the immediate object in view was 
concerned, they show what a delicate and accurate thermometer the galvanometer can 
prove, and that an interesting investigation of the lowering of the melting-point 
temperature of ice''' could be made by using a modification of the above apparatus 
suitable for pressures of two or three hundred atmospheres, such as will be described 
presently. 
Successful Attempts and Results. 
The previous trials having shown that pressures of several atmospheres must be 
resorted to if one was to hope to measure any alteration of resistance which might be 
produced by fluid-pressure, the following apparatus (fig. 15) was employed :—- 
Fig. 15. 
M M is a strong vessel made of gun-metal (drawn to scale in fig. 15 one-sixth of the 
real size), C, B are two binding screws at the ends of two stout brass wires passing 
water-tight through a cover, K K, and separated from the latter by insulating material. 
This cover could be removed at will, and the ends of the wire to be tested, X, X, con¬ 
nected by two small binding screws (shown in the figure unscrewed) A, A, at the lower 
ends of the stout brass wires. After the wire had been well secured to A and A, these 
latter, the wire itself and those portions of the stout brass wires which projected below 
the cover, were well coated with paraffin wax. The vessel having been filled with 
* The effect on the resistance of tlie wire is so very small as to be almost neglectable, and the 
correction even for this can be made by data which are given further on. (See p. 77, Table VI.). 
