On the Effects of < '//"////>:* of Tcnifxr^ttirc on Metal Wires. 18.'> 



Steam was generated under atmospheric pressure in an ordinary 

 boiler, and was led into the upper end of the space by what is called 

 in the diagram the " source-pipe," while what remained uncondensed 

 escaped by the " sink-pipe " below. It was found that the space in 

 which the wire hung was thus heated to a fairly uniform temperature. 

 This temperature was determined by means of four thermo-electric 

 couples of copper and German silver, the arrangement of which is shown 

 in fig. 2. A German-silver wire passes along the axial space close to the 



FIG. 2. 



wire under test, and four copper wires are soldered to it at intervals as 

 shown. These copper wires are led out along the axial space in which 

 the wire hangs. Junction (1) is 25 cm. from the top of the jacket, 

 junction (2) 150 cm. lower down, junction (3) 150 cm. still lower, and 



