y.Frnr of sti?k«s o\ ma^jn'itfza'iidv, 



those used in oiir |»i'('vi(»iis ('X|iciiiii('iils on t lie <'li:iiii;(' (»t li'jiditv 

 hy niagnc'tizcition. 



The stînidardizatioii of llic hallistif ^galvanometer was made 

 lor «acli -el of (»l)S('r\alions, tliongli llic constant rcniaincd f'aiily 

 fonstant duiinii the wliolc; cxiM'riinent, Instead of nsin;;' eaeli 

 tinic tlie sj)ecial coil made foi' the standaidization, we often nsed 

 the compensatin«^ secondary coil foi* a set oï ex]»erinients, lecord- 

 ini; tli<* deflections of the j^alvanorneter corresponding to a scries of 

 ma<i;netizin_i; currents, and at the end of a set, th(i induction of 

 this coil was comj)ared witli the standardizing^ coil. In tliis way, 

 tinxi and lahoiir were economized, without the risk of introducing 

 any sensihle error in the constant of galvanometer. 



? 3. RESULTS OF EXPERIMENTS. 



Tlie intensity of magnetization was' calcidated in the usual 

 manner from the throw of the Inillistic galvanometer with a 

 known constant, the numhers of turns of tlie secondary and thr- 

 standardizing coil, and th(; sections of the specimen wire and i\ut 

 standardizing coil. 'J'he necessary correction for the reduction to 

 tangent was made for considerahle deflections. 'J'he magnetizing 

 field was calculated from tlie reading of the ammeter of known 

 constant, hy use of the known turns of the coil. The demagnetiz- 

 ing force, though it was very small, was also taken into account. 

 Tensions were all reduced to weights ])er square millimeter, and 

 torsions to twists per unit length. 



In the following i)ages, / denotes the intensity of magnetiz^i- 

 tion, //' the external field apj>lied ami 7/ th(Mnternal or effective 

 field, all expressed in C.G.S. units ; T «lenotes the tension in 

 grams per square millimeter, and r the twist in minutes of arc 

 |)er unit of length. * 



