ON THE SILENT DISCHARGE OV ELECTRICITY ON OXYGEN, ETC. 439 



The Influence of the Silent Discharge of Electricity on Oxygen and 

 other Gases. — Report of a Committee, consisting of Professor 

 H. McLeod (Chairman), JMr. W. A. Shenstone (Secretary), 

 Professor W. Eamsay, and Mr. J. Tudor Cundall. (Drawn 

 ivp by the Secretary.) 



This Committee was first appointed in 1885 ; grants of money were made 

 in that and in the succeeding year. The expenditure of these grants 

 has already been duly reported. It therefore only remains to give an 

 account of the work that has been done. This has already been fully 

 described in the ' Journal of the Chemical Society ' and elsewhere, and 

 consequently it will be sufficient now to give an outline of the results 

 obtained, with references to the fuller descriptions. 



I. The Preparation and Storage of Oxygen.^ 



In this note a method of preparing oxygen from a mixture of the 

 chlorates of sodium and potassium was described. The process recom- 

 mended has been found to be very convenient, and has since been adopted 

 by other investigators. Its advantage lies in the ready fusibility of the 

 mixture, and the consequent reduced risk of breaking glass apparatus in 

 which the chlorate must be submitted to repeated fusion and solidification 

 in the course of generating oxygen from it. 



II. Ozone from Pure Oxygen. Its Action on Mercury, with a Note on the 

 Silent Discharge of Electricity.'^ By W. A. Shenstone and J. Tudor 

 Cundall. 



The experiments described in this paper showed that a good yield of 

 ozone (7*5 per cent.) is readily obtained from carefully dried oxygen. 



It has lately been suggested by Professor Armstrong that, in spite of 

 the care taken, it is possible impurity may have been introduced into 

 the gas by the action of the discharge, which might conceivably detach 

 adherent moisture from the glass surfaces of the apparatus. Moreover, 

 when these experiments were made the only liquid that was available for 

 use in the manometers was oil of vitriol, and though this was screened 

 from the dried oxygen by phosphoric anhydride, its use introduced a fresh 

 element of uncertainty. 



On the other hand, the proportion of ozone obtained was, considering 

 the form of apparatus employed, sufficiently high to suggest that the con- 

 ditions of the experiment were very favourable to the production of a 

 high yield of ozone, and the mixture of ozone and oxygen obtained by the 

 discharge was apparently without chemical action on mercury, which is 

 inconsistent with the idea that moisture was present in it, whilst it is 

 stated by Brodie in his ' Classical Research ' that in order to obtain a 

 high yield of ozone dry oxygen must be employed. 



The later experiments described in section III. will make it possible 

 to investigate this point more severely than in 1885, and therefore this 

 important question will very shortly be re-examined. 



' British Assoc. Hej/., 1886. - Journ. Che 



