532 Mr. R. H. M. Bosanquet on Electromagnets. 



Table I. 



Soft Iron Bar. *9379 centim. radius, 28'55 centim. long ; 

 957 windings. 







Force, or 









23. 



P- 



ampere- 

 turns. 



/. 



M. 



m. 





centim. 











25-1 



•343 



Earth 









168 



•315 



420 



•792 



831 



10-7 



414 



•272 



89-5 



•754 



1,959 



24-8 



1,423 



•237 



268-5 



•696 



6,227 



78-9 



2,467 



•238 



467-6 



•767 



12,900 



150-8 



10,210 



•233 



1894 



•754 



48,400 



613-3 



17,214 



•299 



4099 



•798 



86,200 



1093 



17,858 



•331 



4704 



•808 



90,600 



1148 



19,289 



•445 



6832 



•835 



101,100 



1281 



19,650 



•522 



8159 



•854 



105,500 



1337 



The first entry is a mean between determinations made 

 with the horizontal and vertical components of the Earth's 

 force. The magnetic resistance of this bar under H (the less) 

 was in every case less than that under V (the greater). This 

 is opposed to the general run of the values. The mean elimi- 

 nates this inconsistency, which is probably due in some way 

 to residual magnetism. 



Table II. 



Soft Iron Bar. '4800 centim. radius, 30*00 centim. long ; 

 995 windings. 







Force, or 









33. 



P- 



ampere- 

 turns. 



/. 



M. 



on. 



ce 



ntim. 











28-2 



183 



H 









73-5 



177 



V 









541 



117 



50-3 



•726 



679 



31-3 



1,207 



1058 



101-7 



•748 



1,560 



71-8 



1,785 



0846 



137-5 



•704 



2,173 



1000 



5,675 



0850 



384-0 



•726 



7,115 



327-6 



11,113 



0822 



726-6 



•718 



13,800 



635-4 



14,093 



0836 



938-0 



•736 



17,900 



825-3 



18,200 



134 



1938 



•793 



24,900 



1148 



19,411 



180 



2782 



•814 



27,300 



1258 



19,957 



263 



4181 



•869 



30,600 



1380 



21,428 



385 



6559 



•885 



32,800 



1509 



All calculations were made to 5 places, but only so many 

 places are given as seem necessary in each case. 



