348 



Messrs. G. F. C. Searle and T. Gr. Bedford. 



The second view receives a certain amount of support from the fact 

 that such fusions are known in other yeasts, e.g., Saccharomyces 

 Ludwigii (Hans), but in these cases growth is active, and there does 

 not seem to be any nuclear fusion. 



Having regard to the behaviour of the nuclear contents and the 

 subsequent formation of spores, the third view seems most likely. 

 Looking upon the process then as a sexual act of the simplest kind, 

 and in view of the fact that, while all its other characters accord with 

 those of Saccharomyces, it differs from the latter in the manner of its 

 spore-formation, it is proposed to place it in a new genus, Zygo- 

 saccharomyces, on the analogy of the genus Schizo -saccharomyces, 

 suggested by Beyerinck for the fission-yeasts. 



" The Measurement of Magnetic Hysteresis." By G-. F. C. Seaele, 

 M.A., and T. G-. Bedford, M.A. Communicated by Professor 



J. J. Thomson, F.E.S. Eeceived May 2, -Eead June 6, 1901. 



§1. In 1895 one of the authors described* a method of measuring 

 hysteresis by observation of the throw of a ballistic electro-dynamo- 

 meter. The method in its most elementary form is very simple. An 

 iron ring of section A and mean circumference I is uniformly wound 

 with NZ turns of primary winding, and the primary current C passes 

 also round the fixed coils of an electro-dynamometer. A secondary 

 coil of n turns wound on the ring is connected in series with the 

 suspended coil of the dynamometer and an earth inductor, the total 

 resistance of the circuit being S. 



The effects of self-induction in the secondary circuit being neglected, 

 the secondary current c is 



= An (IE 

 ° S dt ' 



If the couple acting on the suspended coil due to the currents C, c 

 be qCc, then at any instant 



since H = 4ttNC, when the magnetic force due to c is neglected. 



If the instrument be used ballistic-ally, the angular momentum 

 acquired by the coil while C changes from Co to - C , is 



(Abstract.) 



Couple = qCc = q 



An „dB 



4ttNS a dt ' 



* G-. F. C. Searle, " A Method of Measuring the Loss of Energy in Hysteresis,'' 

 ' Oamb. Phil. Soc., Proc.,' vol. 9, Part I, 11th November, 1895. 



