sun? A. M. Mayer—Effects of Magnetization 
Examining the results of my experiments on rod 00, of hard 
steel “drawn to blue,” we see that the phenomena are exactly 
the reverse of those occurring in rods of iron in the same cir- 
cumstances, except in this one particular, viz., that after break- 
ing the first made circuit the rod is permanently elongated ; and 
this result agrees with all of those obtained by Dr. Joule. 
The experiments on rod 0, of hard steel “drawn to yellow” 
are noteworthy. On making the first circuit, this rod Tretracted 
1 
one foot long, a quarter of an inch in diameter, tension 80 lbs,” 
with currents deflecting his galvanometer 34° 40 up to 56° 380’; 
ut with currents below 84° 40’ no action whatever was ob- 
served to take place in the rod, except its magnetization; but 
when the same rod was subjected to a tension of 462 Ibs., and a 
elongated more than it had previously retracted when this cir- 
cuit was broken. With a tension of 1,680 bs. the rod retrac 
and elongated by equal amounts on making and breaking the 
circuits. In Dr. Soithc's experiments on a “hardened steel wire” 
one foot long, a quarter of an inch in diameter, tension 80 hbs., 
e observed no effect until the current reached an intensity of 
45° 40’; then this rod also elongated and retracted by equal 
quantities on making and breaking the circuits, With a ten- 
