TRANSACTIONS OF THE SECTIONS. 61 



On the Typical Hydrocarbons, from Marsh-gas to Anthracene, with the 

 Oxidation of the latter into Anthroquinone and Alazarine. By Dr. Mac- 

 Vic ab. 



On Atmospheric Ozone, By T. Moffatt, M.D., F.E.A.S., F.G.8. 

 The results in this paper were deduced from observations extending over a 

 period of twenty years. The author stated that the maximum of ozone occurred 

 with the conditions of the equatorial cui-rent of the atmosphere, and the minimum 

 with those of the polar current. The quantity of ozone is greater in the night 

 than in the day. It varies with the seasons. With thimderstoi-ms, the aurora, the 

 zodiacal light, hail, snow, and sleet, it is above or below the mean quantity, ac- 

 cording to the readings of the barometer. If the readings be increasing, ozone is 

 in minimum quantity ; but if they be decreasing, it is in maximum quantity, with 

 these phenomena. The author does not consider that the electrolytic action of 

 the sunbeam upon water and vegetable essences produces ozone ; it is, however, 

 he states, produced by the action of the sun's rays upon turpentine. He believes 

 phosphorescence to be the chief source of atmospheric ozone ; and from results 

 deduced from a long series of observations on the phosphorescence of the sea in 

 connexion with ozone, he finds tliat the maximum of the latter takes place when 

 the sea is phosphorescent, and the minimum when it is not phosphorescent. 

 From observations taken diuring four passages over the North Atlantic, it would 

 appear, the author states, that the minimum of phosphorescence of the sea and 

 of ozone occur in the " ice-track " and in the proximity of icebergs. 



On the Quantity of Phosphoric Acid excreted from the System in connexion with 

 Atmospheric Conditions. By T. Moffatt, M.D., F.B.A.S., F.G.S. 



The author mentions that in a paper of his on the above subject, read at 

 the Meeting of the British Association last year, he gave the results of ob- 

 servations for each month. These results showed that the maximum quantity of 

 phosphoric acid is excreted under the conditions of the equatorial cm-rent of the 

 atmosphere, and that the minimum takes place with those of the polar cun-ent. 

 Observations continued during the winter months of last year afford similar re- 

 sults, from which the author concludes that the quantity of phosphoric acid formed 

 in the system by the oxidation of the phosphorus in the protein and phosphorated 

 fat of the blood in the peripheral system, and in the limgs, is determined by the 

 pressure of the atmosphere, just as phosphorus is oxidated out of the system. 



On a Neiu Theory respecting the Heating of Liquids. 

 By J. BniKBECK Kevins, M.J). 



On Artificial Alizarine, with Illustrations. By W. H. Perkins, F.R.S., F. O.S. 



Note on Claudet's Process for the Extraction of Silver. 

 By J. Arthur Philiips. 



It has long been known to those engaged in copper-extraction by the wet 

 process that the precipitate produced not only contains a notable quantity of 

 silver, but also traces of gold. No attempt, however, to separate the precious 

 metals, and to turn them to profitable account, had been made up to the com- 

 mencement of the present year, when Mr. F. Claudet patented a process for tho 

 separation of silver from ordinary copper-liquors by the addition of a soluble 

 iodide. 



The amount of silver present in burnt ore seldom exceeds 18 dwts.^per ton ; and 

 as the whole of this is never obtained in solution, it foUows that, in order to ob- 

 tain satisfactory commercial results, the process employed should be both cheap 

 and expeditious. 



