424 Mr. W. Brown on the Effects of Percussion and 



piece of wood by means of soft copper wire, and annealed for 

 one hour in a bath of linseed oil at a temperature of 100° C. 



They were then taken out and allowed to lie at the ordinary 

 temperature of the room (8° C.) for a period of 6 hours, 

 after which they were magnetized with the same battery- 

 power, and every precaution taken, as formerly. Then, after 

 lying aside undisturbed for a period of 20 hours, they were 

 put through a similar series of observations for the purpose 

 of finding the effects of percussion in changing their magnetic 

 moments. The results are given in the following Table: — 



Table IV. (Annealed for one hour at 100° C.) 



Specimen I. 



Number of 

 magnet. 



Magnetic 

 moment, 

 per gram. 



Percentage loss due to 

 falling 



Total loss. 



one time. 



three times. 



1 



2 



3 



4 



5 



63-4 

 62-4 

 61-7 

 62-6 

 61-4 



0-76 

 1-94 

 '2-74 

 1-54 

 1-97 



1-92 

 0-39 

 0-60 



0-78 

 1-20 



2-67 

 2-32 

 3-33 

 2-70 

 3-19 



Mean 



623 



1-79 



0-98 



2-84 



Specimen II. 



l 



2 



3 



4 



5 



71-2 

 72-1 

 72-1 



72-4 

 72-4 



1-74 

 2-57 

 3-43 

 1-71 

 299 



1-33 

 1-32 

 0-89 



0-87 

 0-88 



2-67 

 3-86 

 4-29 

 2-56 



3-85 



Mean 



7204 



2-49 



106 



3-45 



Specimen III. 



1 



2 



3 



4 



5 



66-8 

 69-8 

 651 

 67-4 



68-3 



2-54 

 2-54 

 4-09 

 2-63 

 216 



0-92 

 1-74 



2-37 

 1-80 

 1-33 



4-42 

 424 

 6-36 

 4-38 

 3-46 



Mean 



67-5 



2-79 



1-63 



4-57 



From the above Table we see that annealing for one hour 

 in an oil-bath at temperature 100° C. has slightly raised the 



