Susceptibility of Iron in Colloidal Solution. 



265 



electromagnet. Curve II, which shows the values of the field 

 plotted against the current, enables us to deduce the field 

 corresponding to a given current through the magnet. The length 

 of the horizontal portion of the tin-foil strip was 327 cms. 



13000 



10000 



o 



Amps 



Curve II. 



2. Susceptibility of Methyl Alcohol. 



In order to determine this we have again to make two sets of 

 readings, firstly, the values of the forces exerted on the empty cell 

 by any field, and secondly, the analogous values for the cell full of 

 alcohol. 



Table IV, which is exactly analogous to Table I, shows that 

 the empty glass cell is slightly paramagnetic. 



Table IV. 

 Susceptibility of Empty Glass Cell. 



Current in Electromagnet 



Weight in Pan 



Pull due to Field 



amperes 



8 



9-9 „ 

 11-75 „ 

 14-95 „ 



o 



45-8963 grams 

 45-9063 „ 

 45-9070 „ 

 45-9080 „ 

 45-9095 „ 

 45-8963 „ 



+ -0100 grams 



+ •0107 „ 

 + •0117 „ 

 + •0132 „ 



The cell was removed, filled with methyl alcohol, sealed up 

 and a similar series of readings taken for the full vessel. These 

 are given in Table V. 



