434 M.J. Janrin on the Theory of the Normal Magnet, and 



2/=310. 



Distance to 



1 



2 



3 



5 



6 



8 



12 



Calcu- 



the centre. 



plate. 



plates. 



plates. 



plates. 



plates. 



plates. 



plates. 



lated. 



millims. 



grras. 



grms. 



grras. 



grms. 



grms. 



grms. 



grms. 



grms. 



155 



125 



221 



28-0 



35-5 



370 



38-4 



37-8 



354 



145 



8-5 



15-0 



207 



307 



30-2 



30-5 



340 



323 



125 



40 



7-6 



167 



21-2 



24-3 



235 



25 



240 



105 



1-5 



4-5 



10-2 



150 



180 



18-5 



180 



16-9 



85 



0-6 



20 



75 



10-0 



127 



156 



142 



10-8 



55 





0-6 



25 



50 



7'1 



70 



76 



4-5 



35 







1-4 



30 



3-5 



3-2 



30 



14 



15 







02 



0-5 



0-5 



07 



1-5 



0-3 



2Z=250. 



Distance to 



1 



2 



3 



4 



7 



11 



30 



Calcu- 



the centre. 



plate. 



plates. 



plates. 



plates. 



plates. 



plates. 



plates. 



lated. 



millims. 



grms. 



grms. 



grms. 



grms. 



grms. 



grms. 



grms. 



grms. 



125 



14-5 



24-6 



28-2 



28-6 



31-6 



276 



29-6 



29-6 



105 



100 



127 



16-2 



187 



18-2 



197 



199 



20-9 



75 



30 



70 



8-6 



11-2 



11-2 



11-2 



11-2 



10-4 



25 





10 



15 



1-4 



1-4 



1-4 



1-4 



1-2 



21= 200. 



Distance to 

 the centre. 



1 plate. 



2 plates. 



3 plates. 



4 plates. 



6 plates. 



Calculated. 



millims. 



grms. 



grms. 



grms. 



grms. 



grms. 



grms. 



100 



100 



20-0 



26-5 



25 



25 



240, 



90 



6-0 



13-5 



135 



20-5 



20-8 



194 



70 



3-2 



8-9 



11-2 



12-4 



130 



117 



50 



20 



50 



75 



6-9 



70 



6-0 



20 



0-4 



10 



17 



1-4 



15 



0-9 



2/=100. 



Distance to 

 the centre. 



1 plate. 



2 plates. 



3 plates. 



5 plates. 



Calculated. 



millims. 



grms. 



grms. 



grms. 



grms. 



grms. 



50 



7-6 



97 



11-4 



127 



120 



40 



47 



7-0 



77 



7-8 



76 



30 



34 



5 5 



5 5 



5 5 



4-3 



20 



1-5 



2-5 



20 



1-8 



106 



10 



... 



1-5 



0-4 



04 



0-4 



III. It is difficult to say at what number of plates the maxi- 

 mum is reached, since it is only slowly arrived at; but it is 

 evident that the number is greater the greater the length. 

 Three or four are required for 100 millims., six to eight for 200, 



