I04 



NA TURE 



\Pec. II, 1873 



and other mountainous districts many other suitable 

 places might no doubt be found. 



Would it not be possible to secure funds for establish- 

 ing at least one such atmospheric section on the slope of 

 some steep hill or mountain in connection with a station 

 or two on an adjoining level district of country ? 



Thomas Stevenson 



ON THE PHYSIOLOGICAL ACTION OF 

 OZONE 



AT a meeting of the Royal Society of Edinburgh on 

 the 1st inst., a communication was read from Mr. 

 Dewar and Dr. M'Kendrick on the physiological action 

 of ozone. The authors, in the first place, pointed out 

 that little was known regarding the action of this sub- 

 stance, except its peculiar smell and the irritating effect it 

 had on the mucous membrane of the respiratory tract. 

 Schonbein had shown that a mouse died in five 

 minutes in an atmosphere highly charged with ozone ; 

 and it was this distinguished investigator who asserted 

 that there was a relation between the quantity of ozone 

 in the air and the prevalence of epidemic diseases. The 

 action of ozone was therefore a subject to be elucidated ; 

 and having occasion to employ ozone in another experi- 

 mental inquiry, the authors resolved to investigate the 

 matter. The ozone wis made by passing a current of 

 dry air or oxygen from a gasometer through a narrow 

 glass tube, bent for convenience like the letter U, about 

 3 (t. in length, and containing a platinum wire 2 ft. in 

 length, which had been inserted into the interior of the 

 tube, and one end of which communicated with the out- 

 side through the wall of the tube. Round the whole ex- 

 ternal surface of this U-shaped tube, a spiral of copper 

 wire was coiled, and the induction current from a coil 

 giving half-inch sparks was passed between the external 

 copper to the internal platinum wire, so as to have the 

 platinum wire as the negative pole in the interior of 

 the tube. After the stream of gas was ozonised by the 

 transmission of the induction current, it was washed by 

 passing through a bulb-tube containing caustic potash, 

 when air was employed, or water when pure oxygen was 

 used, in order to eliminate any traces of nitrous and nitric 

 acids that might have been formed. By means of the 

 gasometer, the volume of gas passing through the tube 

 could be ascertained. 



The action of ozone was determined (i) on the living 

 animal enclosed in an atmosphere of ozonised air or of 

 ozonised oxygen ; and (2) on many of the individual living 

 tissues of the body. Numerous experiments were made 

 on frogs, birds, mice, white rats, rabbits, and on the 

 authors themselves. Two experiments may be given here 

 as illustrating the action of ozone on (i) a cold, and on 

 (2) a warm-blooded animal. 



I. On a Frog. — A large, healthy male frog was intro- 

 duced into the air chamber, through which a current of 

 air was passing sufficient to fill a litre jar in three minutes. 

 At the end of two minutes, the respirations were ninety- 

 six per minute. The induction machine was then set to 

 work so as to ozonise the air. In half a minute, the eye- 

 balls were retracted, so as to appear deeply sunk in the 

 orbits, and the eyelids were closed ; the respirations were 

 now eight per minute. At the end of six minutes, the 

 animal was motionless, and there were no respiratory 

 movements. Pure air was then introduced. In half a 

 minute, there was a slight respiratory movement, and in 

 eight minutes there were eighty five respirations per 

 minute. At the end of other twelve minutes, ozone was 

 again turned on, with the same result. A frog will sur- 

 vive in a dormant condition in an atmosphere of ozonised 

 air for several hours In one case, the anim.al died. The 

 heart was found still pulsating. It was full of dark blood. 

 The lungs were slightly congested. The blood was 

 venous throughout the whole body. In ozonised oxygen 

 the effects were, on the wliole, the same as in ozonised 



air, with this difference, that in ozonised oxygen the 

 respiratory movements were not affected so quickly, and 

 were never completely arrested. 



2. On a V\ hit c Mouse. — A full grown and apparently 

 healthy white mouse was introduced into a vessel tlirough 

 which a stream of air was passing at the rate of eight 

 cubic inches per minute. Five minutes thereafter, the 

 animal was evidently at ease, and the respirations were 

 over 100 per minute. The air was then ozonised. One 

 minute after, the respirations were slower, but the number 

 could not be asceitained owing to the animal moving 

 uneasily about. In four minutes from the time of the 

 introduction of the ozone, the respirations were thirty-two 

 in a minute. The mouse now rested quietly, occasionally 

 yawned, and, when touched by a wire, moved, — but 

 always so as to remove its nose from the stream of 

 ozonised air. At the end of fifteen minutes, the animal 

 had slight convulsive attacks, which increased in severity 

 until it died — nineteen minutes after the introduction of 

 the ozone. The post-mortem appearances were great 

 venous congestion in all parts of the body. The heart 

 pulsated for several minutes after systemic death. In 

 ozonised oxygen, death was delayed for a much longer 

 period. Instead of dying at the end of fifteen or twenty 

 minutes, as happened to mice in ozonised air, they lived 

 for forty or sixty minutes. It is noteworthy that even 

 after death in ozonised oxygen, the blood was found to be 

 in a venous condition. 



On breathing an atmosphere of ozonised air themselves, 

 the authors experienced the following effects : — a suffo- 

 cating feeling in the chest ; a tendency to breathe slowly ; 

 irritation of the fauces and glottis ; a tingling of the skin 

 of the face and conjunctiva. The pulse became feebler. 

 The inhalation was continued for eight minutes, when 

 they were obliged to desist ; and the experiment was 

 followed by violent irritating cough and sneezing, and for 

 five or six hours thereafter by a sensation of rawness in 

 the throat and air-passages. 



The general result of the inquiry may be briefly stated 

 as follows : — 



1. The inhalation of an atmosphere highly charged 

 with ozone diminishes the number of respirations per 

 minute. 



2. The cardiac pulsations are reduced in strength and 

 this organ is found beating feebly after systemic death. 



3. The blood is found after death to be in a venous 

 condition, both in those cases of death in an atmosphere 

 of ozonised air and of ozonised oxygen. 



4. The inhalation of an ozonised atmosphere is followed 

 by a lowering of the temperature of the body to the extent 

 of at least 3° to 5° C. 



5. The inhalation of ozone does not exercise any appre- 

 ciable action on the capillary circulation, as seen in the 

 web of the frog's foot under the microscope (200 dia- 

 meters). 



6. In the bodies of frogs killed in an ozonised atmo- 

 sphere, the reflex activity of the spinal cord is not appre- 

 ciably affected. 



7. By means of a myographion, the work done (in 

 gramme-millimetres) by the gastronemius muscles of 

 frogs subject to the action of ozone was noted. The 

 muscles were stimulated by a single opening or closing 

 induction shock produced by Du-Bois-Reymond's appa- 

 ratus and a Daniell's cell. The result was that the con- 

 tractility and work-power of the muscle were found to be 

 unaffected. 



8. Ozone has an action on the coloured and colourless 

 corpuscles of human blood and of frog's blood resembling 

 that produced by a weak acid; and in the case of the 

 coloured corpuscles of the frog like that of a stream of 

 carbonic acid. The corpuscles of animals killed in an 

 ozonised atmosphere are normal in appearance. 



9. Ciliary action is not affected by a stream of ozonised 

 air or oxygen, provided there is a considerable amount of 



