PHYSIOLOGICAL INFLUENCE OF OZONE HILL AND FLACK. 623 



Fat has a power of absorbing ozone until it smells strongly of 

 ozone, and it retains the ozone for a long time. Mr. F. Kidd kindly 

 tried for us the application of ozonized lard or vaseline to foul chronic 

 ulcers of the leg, but found that while hot fomentations were effica- 

 cious in cleaning up and rendering sweet control cases of ulcer, the 

 ozonized ointment had little effect. 



For the investigation of the respiratory metabolism we used the 

 Haldane-Pembrey gravimetric method. Mice or small rats were 

 placed in a beaker fitted with a thermometer and the beaker placed 

 in a Hearson air bath to keep the external temperature constant. 

 In a first series of experiments the ozone was generated by a specially 

 made small ozonizer, and led partly through the animal chamber 

 and partly through a collecting wash bottle, in order that its con- 

 centration might be determined. 



The water vapor given off by the animal varied so much with the 

 passing of urine and feces, and possibly with the animal putting up 

 its fur, as it does when depressed by the ozone, that we can lay no 

 weight on the calculation of oxygen intake. The weakness of the 

 gravimetric method lies in the fact that the oxygen is calculated 

 from the difference between loss of body weight and output of water 

 and C0 2 , and not directly measured. 



We shall confine our considerations in these experiments to the 

 loss of body weight, and the C0 2 output. Table II shows the loss 

 of weight sustained by the animal, the amounts of H 2 and CO, 

 given off before, during, and after ozone. It is seen that there is a 

 marked depression during and after the administration of ozone. 

 The table gives a random selection made from 25 similar experiments. 



The figures for the loss of weight represent the loss of weight of 

 the animals weighed in the respiration chamber. Evaporation of 

 urine and feces when passed contribute to this loss. As the loss of 

 body weight is also influenced by the passing and evaporation of 

 the urine and water from the feces, the C0 3 output results are the 

 more trustworthy. 



As the concentration of ozone given by the small generator seemed 

 to be too high, we obtained the ozone in the following experiments 

 by generating it in a room, the ozonizer being placed at distances 

 varying from 100 to 350 cm. from the inlet of the ventilation current 

 which was drawn through the animal chamber. Table III gives the 

 loss of weight and amount of C0 2 given off in milligrammes in the 

 last eight experiments made under these conditions, the reading for 

 the oxygen as before being variable. In all, 16 similar experiments 

 were made on small rats. 



