[March, 
148 The Lines of Discovery in the 
found chlorine . Since ozone is so slightly soluble in water 
at common temperatures that it is extremely difficult to 
demonstrate the fadt of solution, the proposition to employ 
6i ozonised water ” as a remedial agent opens a wide door to 
quackery. 3rd. It is certain that from the mixture of 
potassium permanganate and sulphuric acid, which has been 
and is recommended as a convenient source of ozone for 
medical use, no ozone, but merely chlorine and oxides of 
chlorine (due to impurities in the permanganate) are 
derived. 
These errors have been exposed and the difficulties over- 
come. There is no obstacle to having in the office of the 
physician, the sick-room of the patient, or the wards of the 
hospital, ozonisers suitable to each place, and adequate to 
supply ozonised air or oxygen of known strength and purity. 
This being the case it remains for the therapeutist to do 
his part of the work, and to discover when and how ozone 
is to be employed in legitimate practice. 
Second, to detect the amount of ozone present at any 
time or place in the atmosphere, and the role this atmo- 
spheric ozone plays as a disease excitant or prophylactic. 
The objections which vitiate the observations hitherto 
made are two in number 1st. The ozonoscopes hitherto 
employed, Houzeau’s and the thallium-test included, are all 
affected by some one of the gaseous bodies possibly present 
in the atmosphere, as well as by ozone. 2nd. The method 
of conducting the observations is in its nature inexact, and 
variations in wind, temperature, humidity, &c., are allowed 
to increase the resultant errors. 
Advance in this direction is to be looked for only when 
the methods at present in use are abandoned in favour of 
others more in harmony with those pursued in other 
branches of gas analysis, and when reagents are employed 
which will assign true values to the amounts of ozone 
determined. 
II. The Nature of the Constituent Matter of Ozone . 
In his speculations upon the nature of ozone, Schonbein 
was far less fortunate than in his multiplied inquiries into 
its sources, properties, and applications. The difficulty at 
that time of procuring air or oxygen containing more than 
a minute percentage of ozone, and of manipulating it when 
obtained, was very great, so that precise quantitative inves- 
tigations were attended with formidable obstacles, and 
probably for that reason were rarely instituted by Schonbein. 
