690 
for some distance. If the temperature was then kept constant, the 
E.F. decreased till the stable branch was reached (see the points 
OE Or Es U, 4): 
In the second place tin was combined with copper, in which the 
following result was reached. 
When these results are again represented graphically, the transi- 
tion point of tin again makes its appearance at 200°.5, in agreement 
with what precedes, but less clearly here. This is seen in fig. 2. 
When in this way the reliability of this sensitive and rapid 
method had been proved, we applied it to ascertain whether 
in copper indications for a transition point could be observed in 
the neighbourhood of 70°. As is known, the dilatometrie investi- 
gation *) gave no indication at all, no more than BRIDGMAN’s researches. 
The result of this investigation will be discussed in a following paper. 
Laboratory of general and inorganic chemistry of 
the Amsterdam University. 
Amsterdam, May 23'd 1920. 
1) CoHEN, These Proc. Vol. XVI, p. 628. (1914). Z.f. phys. Chem. 87, 419 (1914). 
