ON THE SILENT DISCHAKGB OF ELECTRICITY. 55 



charge in apparatus so constructed that the whole mass of the gas was, 

 practically, simultaneously exposed to the action of the discharge ; hence 

 the maximum effect was quickly arrived at. The amount of ozone formed 

 was calculated (on the assumption that the density of its original ozono 

 is 24) from the pressure at which the gas occupied unit volume before 

 and after the action of the discharge. The discharge from a large 

 Ruhmkorff coil was used. 



The results obtained varied exceedingly. Under what appeared to bo 

 nearly identical conditions the yield of ozone was sometimes almost 

 nominal, at others fairly good ; whilst on one occasion nearly 20 per 

 cent, of the oxygen employed appeared to have been converted into ozone. 

 Subsequent experiments showed us that this was probably caused by the 

 very variable action of the contact-maker of the coil, and it was therefore 

 necessary to devise and construct a new contact-maker which should act 

 with great regularity and be subject to perfect control. This involved 

 considerable delay, and, unfortunately, just as the new apparatus was 

 completed circumstances compelled us to suspend operations for many 

 months. 



Lately, however, work has been resumed, and the results since obtained 

 justify the hope that our difhculties are now overcome. We hope, there- 

 fore, that at the next meeting of the Association we shall have made 

 substantial progress with the investigation. 



Since our last report was printed an interesting paper on ozone has 

 been published by MM. Bichat at Guntz.^ Some of their work bears upon 

 the points we are investigating, and, as in some respects their results 

 may seem not to offer us much encoui'agement, it is worth while to add 

 tiiat our method of experiment seems to us to be in certain respects better 

 than that adopted by these investigators, and that consequently we still 

 see good reason to hope for ultimate success. 



Report of the Committee, consisting of Professors Dewar, E. Frank- 

 land, Percy F. Frankland (Secretary), and Odling and Mr. 

 Crookes, ajopointed to confer %uith the Committee of the Ameri- 

 can Association for the Advancement of Science xvith a view of 

 forminrj a uniform system of recording the results of Water 

 Analysis. 



Having during the past two years given this matter our careful con- 

 sideration, we beg herewith to submit the following report. 



In order to ascertain the general feeling of chemists in this country 

 on the subject, we have circulated the following series of questions 

 amongst the leading water-analysts, upon whose co-oj^eration the adoption 

 of any uniform scheme must necessarily depend. 



1. What is the system of recording the results of Water Analysis 

 whicli you adopt ? 



(a) For the Mineral matters. 

 {h) For the Organic matters, 

 (c) For the Gaseous matters. 



' Comjftes rendus, 1888. 



