Recent Progress in Sanitary Science. 273 



potassium iodide contained several impurities, rendering it 

 unfit for use in the ozone test ; and that even the starch had 

 to be manufactured in the laboratory, to obtain material suita- 

 ble for preparing reliable reagent papers. And yet, with 

 suitable precautions, these ozone tests give results of a very 

 striking character. As an instance, I may cite some unpub- 

 lished observations during the past summer upon the atmos- 

 phere of the Adirondacks, where the indications of ozone were 

 of the most decided character, and at times of atmospheric 

 disturbance, intense. In this pure mountain air, the invalid, 

 prostrated with malarial poison, or catarrhal affection, rap- 

 idly regained mental vigor and bodily strength. Similar 

 ozone tests, exposed during the same season in Hoboken, 

 where catarrhs are rife, and where the badly drained marshes, 

 if they do not actually produce ague, are at least very un- 

 favorable to recovery from it, showed a great deficiency in the 

 amount of ozone. 



I do not wish to be understood as saying that the absence 

 of ozone is attended by the prevalence of catarrhal or mala- 

 rial troubles. Heaven forbid ! The result of collecting and 

 reading most of the literature upon ozone, has been to make 

 me extremely unwilling to express any opinion, concerning 

 the connection between the abundance or exiguity of ozone 

 and any disease whatsoever. The conflict of testimony could 

 not be better exemplified than in the case just under con- 

 sideration. To quote from a recent work on the subject — 

 " Schonbein and other physicians made daily atmospheric 

 observations during several catarrhal epidemics at Basle, 

 which are stated to have been conclusive as to the simul- 

 taneity of the maximum of the coloration with the extreme 

 intensity of the epidemic." "Dr. Seitz carried on observa- 

 tions for two years in Munich, and found that months in 

 which the ozone was abundant, were not characterized by a 

 predominance of catarrhal affections, when compared with 

 months during which less ozone was noticed in the air. 

 After days distinguished by a great excess of ozone, we did 



