32 Prof. Threlfall and Messrs. Brearley and Allen. [May 24, 



May 24, 1894. 

 The LORD KELVIN", D.C.L., LL.D., President, in the Chair. 



Professor fileuthere filie Nicolas Mascarfc, who was elected a 

 Foreign Member in 1882, signed the Obligation in the Charter Book, 

 and was admitted into the Society. 



A List of the Presents received was laid on the table, and thanks 

 ordered for them. 



The following Papers were read : 



I. " Researches on the Electrical Properties of Pure Sub- 

 stances. No. I. The Electrical Properties of Pure Sulphur." 

 By *RIOHARD THRELFALL, M.A., Professor of Physics in 

 the University of Sydney; JOSEPH HENRY DRAPIER 

 BREARLEY, Deas-Thomson Scholar in the University of 

 Sydney, and J. B. ALLEN, Exhibition Commissioners' 

 Scholar of the University of Adelaide, South Australia. 

 Communicated by Professor J. J. THOMSON, F.R.S. Re- 

 ceived April 19, 1894. 



(Abstract.) 



Since there appears to be no definite information as to the elec- 

 trical properties of pure elemental substances which are not metals, 

 an attempt has been made to provide the necessary data in the case 

 of sulphur. This element was chosen as being capable of easy puri- 

 fication, and because it can exist in a variety of forms, from the 

 comparison of the electrical behaviour of which some information 

 was expected to be obtained. The experimental work was begun in 

 1886, and some preliminary results were published by one of the 

 authors and Mr. J. A. Pollock in the ' Philosophical Magazine ' for 

 1890. These results referred to the construction of galvanometers 

 for high resistance measurements, the reliability of the Clark cell as 

 a source of small constant currents, and a method of using the gal- 

 vanometer in resistance measurements in such a way that no 

 galvanometer law of current measurement needs to be assumed. 



* Part I by Professor Threlfall and Mr. Brearley. Part II by Professor Threl- 

 fall and Mr. Allen. 



