M \(.\Tri'rZ\'l'TO\ uF XTi'KKT,. 29F) 



nnalogoiis lo ihc pivccdiiii;' twD cîises, as •.\ fiance ;i( Fiii's. L'], 11, 

 and 15 will show. From Figs. 15, 16, 17. however, we see how 

 the opposite magnetization becomes smaller as we increase the field. 

 The i-ati() + vi/( — !>\) is iihvays a very large ([iiantity ami has a 

 minimum .value for a particular load. For loads greater than this 

 particular load, the negative magnetization decreases, and at last com- 

 pletely vanishes. Thus lor stress jr=1770 kgs.. there is no opposite 

 magnetization therein agreeing with the curves for loads snialler than 

 that for which the negati\ e magnetization first appears. But there is 

 the dift'erencc that the curve is a single loop in which ^Ks/'^sr changes 

 sion during negative twisting and untwisting. 



Taking into account all the series of experiments, we sec that the 

 greatest value iu each series of the ratio +rs/— ITv tends to increase 

 as the field is increased. The strength of field in which these last 

 experiments were tried seems to be about the critical value for which 

 uc can get the two transitions oi' magnetization — namely the change 

 of sign for i)nrti<-iilar load and the vanishinüf of this chano'C for a 

 higher load. 



The peculiarities, which have just Ijeen the subject of discussion, 

 do nor however persistât all strength of fields. At still higher fields, 

 a different order of things comes in. Take for example the next series 

 of experiments with a field of .S.OG, as shown in Figs. 18. 19. 20, 

 '21, '2'2. First of all, for the lower tensions, the two-looped curve is 

 more symmetrical than it can be obtained at lower fields (see Fig. IS.) 

 In Fig. 1 !), for a tension of 78:^. a symmetrv l)egins to show itself; 

 l)ut the diminution instead of taking i)lac(' in the left hand i>r negative 

 Iciop, takes place in the right hand or positive loop. I*"igs. 20. 21, 

 show the gradual vanishing away of this right liand loop as the load 

 is increased. Also, exactly as in the former sets of experiments, the 

 curve ilip>j below the zero magnetization line, as the right hand portion 



