496 MR. J. B. LAWES, DR. GILBERT, AND DR. PUGH ON 
of the Ozone. Thus, all the ozonized air passed the wash-bottle in its course from the 
balloons to the distributing apparatus. 
The following substances were subjected to the action of the Ozone—each substance, 
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) 21b. of ignited soil, moistened with 100 cub. centims. water, this being just sufficient 
to make it slightly coherent. 
(2) 21b. of ignited soil, 300 cub. centims. water, 2°5 ounces boiled starch, and 2°5 ounces 
dry starch. 
(3) 2b. of ignited soil, 200 cub. cenitms. water, and 2-5 ounces saw-dust. 
(4) 2:6 ounces saw-dust, and 100 cub. centims. water. 
(5) $b. of ignited soil, 200 cub. centims. water, and 2°5 ounces bean-meal. 
(6) 21b. 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) 1b. garden-soil. 
(9) 21b. of slaked lime, and 2°5 ounces bean-meal, made slightly pasty with water. 
(10) £1b. 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. water. 
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 hows. 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° 
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 
