496 ME. .1. B. l-AWl.x DR. GILBERT, AND DR. PI GB 



of the Ozone. Thus, all the ozonized di passed the wash-bottle in its coot e Gram the 



balloons to the distributing apparatus. 



The following substances were subjected to die action of the Ozone — each in 

 or mixture, being enclosed in a glass bottle of about 1/5 litre capacity, fitted with an 

 exit-tube in which were fragments of pumice saturated with sulphuric acid : — 



(1) Jib. of ignited soil, moistened with 100 cub. centims. water, this being just sufficient 

 to make it slightly coherent. 



(2) 5 11). of ignited soil, 300 cub. ecu tin is. water, 2*5 ounces boiled starch, and 2*5 out 

 dry starch. 



(3) fib. of ignited soil, 200 cub. cenitms. water, and 2*5 ounces saw-dust. 



(4) 2'f> ounces saw-dust, and 100 cub. centims. water. 



(5) I lb. of ignited soil, 200 cub. centims. water, and 2-5 ounces bean-meal. 



(6) | lb. of ignited soil, 150 cub. centims. water, and 2-5 ounces bean-meal. 



(7) 2 - 5 ounces bean-meal, and 50 cub. centims. water. 



(8) 1 lb. garden-soil. 



(9) fib. of slaked lime, and 2-5 ounces bean-meal, made slightly pasty with water. 



(10) fib. of slaked lime, some starch, and saw-dust, made slightly pasty with water. 



(11) 2-5 ounces of boiled starch, 2-5 ounces fresh starch, and 200 cub. centims. wafa i . 

 All the bottles were placed before a window where the sun shone directly upon them 



for a considerable part of the day, as it did also for some hours daily upon the 

 balloons. 



Every day, about 9 o'clock in the morning, the cylinder of the gasometer was raised, 

 and a slow current of air passed through the apparatus during about two hours. This 

 process was generally repeated once or twice more during the day. The experiment 

 commenced in April, and continued till the following autumn ; that is. through all the 

 warm weather of the summer, when a thermometer in the room frequently stood at 25 e 

 to 29° C. The amount of Ozone passing through the apparatus was so great, that the 

 vulcanized caoutchouc which connected the tube from the last balloon with that passing 

 into the wash-bottle was cut off with the passage of three or four gasometerfuls of air. 

 The joint was then made by fixing a piece of larger glass tubing over the point of contact 

 of the smaller connecting tubes, and closing the ends of the larger tube with corks well 

 fitted upon the smaller ones. 



Once every three or four days a small piece of phosphorus was dropped into each 

 balloon. In this way the action was sufficiently maintained to produce a distinct odour 

 of Ozone in the room whilst the air was passing. 



During the first half of the period of the experiment, a wash-bottle filled with large 

 lumps of pumice, and about half-full of a solution of caustic potash, was used ; so that 

 the ozonized air in bubbling rapidly through the solution continually threw it up, by 

 which means the pumice was kept moistened with it. 



A careful examination of this liquid, together with the washings of the pumice, failed 

 to detect any nitric acid. About the 1st of July, the alkaline wash was replaced by a 



