HALL. — THERMO-ELECTRIC HETEROGENEITY IN ALLOYS. 563 



20 30 



Figure 8. 



its length at once is not necessarily stretched equally at all parts; for 

 example, the point which had been the 50 cm. point before the stretch- 

 ing might not lie, and in our observations usually did not lie, just 

 half-way between the points which had been the 25 cm. and the 75 cm. 



