240 
IOWA ACADEMY OF SCIENCE Vol. XXIV, 1917 
It is thus seen that the specific resistance increases as the 
density due to drawing increases, P. W. Bridgman 1 finds that 
the resistance of tungsten decreases as the density due to hydro- 
Radius tin.es 10^ Co.. 
Figure 40 
static pressure increases. This also indicates that the drawing 
has some sort of a surface effect and not a volume effect as is 
the case in Doctor Bridgman’s work. 
Physical Laboratory, 
The State University. 
hFrom lecture given at the State University of Iowa on April 18, 1917 
