616 Prof. Richardson and Mr. Lownds on the Magnet 



w 



H= 



8-2. 



H=348. 



T. 



E. 



T. 



B. 



696 



168 



696 



106 



638 



274 



638 



1^2 



582 



1027 



580 



292 



564 



1567 



544 



637 



541 



19 10 



500 



1123 



500 



2195 



477 



1291 



474 



2319 



450 



1397 



452 



2380 



428 



1451 



428 



2425 



408 



1520 



408 



2495 



394 



1647 



394 



2780 



3S8 



1813 



386 



3035 



369 



1990 



3(59 



3265 



360 



1990 



360 



3320 



354 



1990 



354 



3320 



326 



1902 



330 



3328 



293 



1795 



291 



3293 



235 



1505 



235 



3185 



152 



1274 



152 



30S2 



20 



1045 



20 



3015 







The specimen was next slowly heated to 434° C. and then 

 slowly cooled, double-re vesal throws being taken at intervals; 

 the readings (not given) were found to lie on the last curve 

 obtained. 



The specimen was then unwound and rewound with cotton- 

 covered copper wire soaked in melted paratiin, and double- 

 reversal throws were taken at ordinary temperatures. The 

 values obtained confirmed the preceding observations. 



The ring was now wound with asbestos-insulated copper 

 wire, the number of turns in the primary and secondary 

 being the same as in the previous experiments with asbestos 

 insulation. 



The specimen was then heated by stages to 720° C. and 

 cooled, double reversals being taken at each stage when the 

 temperature was steady. This experiment lasted 36 hours. 



These values are indicated on the diagram thus : — 



O 



for observations during heating, 



for observations during cooling. 



