244 



MR J. C. BEATTIE ON THE 



Plate II. 



Length, 

 Breadth, 

 Thickness, 



16-5 

 8-0 



irl 



mm. 



n=-83 

 Temp. 9° C. 



c 1 (A»)i + c 2 (Aw)5= -E. 



Field 

 in cgs. 

 Units. 



Trans. 

 Effect. 



a 

 An 



J An 



An J A 7i 



y 



An J A n 



a 



c 1 c 2 



y 



1,170 



- 4087 



•0110 



•1049 





... 









1,840 



-•1270 



•0150 



•1279 









... 





2,520 



- -2220 



•0460 



•2145 







-1-04 +'30 







3,180 



- 3249 



•1041 



•3229 



•1018 3190 





-1-04 +-30 



-1-05 +-32 





5,030 



- 3840 



•1499 



•3872 





•2865 -5352 



-104 +-30 







8,500 



- 5147 



•2945 



•5427 





•5696 -7540 



-1-04 +-31 





-•74 +1-2 



9,500 



- 5264 



•3130 



•5594 







-104 +-30 







11,740 



- 5679 



•3756 



6129 



•3805 6163 



•7577 -8704 



-104 +-30 



-1-04 +30 



-•74 +1-1 



12,840 



- 6075 



•4573 



6761 







-1-04 +-30 







14,200 



-•6181 



•4919 



7013 



•4820 -6944 





-1-04 +-30 



-1-04 +-28 





15,600 



- 6302 



•5300 



7215 







-1-04 +"30 







17,780 



- -6600 



•6081 



7798 



•6023 -7716 



1-0062 10031 



-1-04 +-30 





-•75 +1-2 



- 











Average, 



-104 +-31 



-1-04 +31 



-•75 +1-2 



In Plate IX. the relation between the transverse effect arid the resistance variation 

 perpendicular to the field was alone considered. Owing to the size of the plate the 

 arrangement — e — was somewhat different. The plate was fixed on to stiff cardboard, 

 the transverse electrodes were soldered to the middle points of the sides, the primary 

 electrodes to the middle points of the ends. The plate was then placed with its surface 

 perpendicular to the lines of magnetic induction and kept clamped in this position. 



We see that in these two plates we have not to deal with a pure Hall effect only ; 

 we have in addition a second effect, which is positive and proportional to ( Anf that is to 

 the magnetisation cubed. 



The results for Plate IX. and for all the plates showing two effects can be 



represented graphically ; the resistance variation is measured along the horizontal axis. 



-E . . 



Along the perpendicular axis the values of — are laid down ; the connecting curve is 



a straight line, which, when produced to meet the perpendicular axis, gives the value 

 of Cj. To obtain such a curve for any plate, at least two direct measurements of the 



