242 ANNUAL OF SCIENTIFIC DISCOVERY. 



shaded by dark-colored glass and during the night. When snow fell, 

 Dr. Polli observed its action to be very powerful, as also during the 

 prevalence of northern winds, and rainy and cloudy days. When fine 

 weather had lasted many days, the air became loaded with ozone, but 

 immediately after heavy showers it disappeared ; slips which before 

 the rain appeared were colored in a few hours, then remaining white 

 for days. After the rains have ceased the ozone reappears, and con- 

 tinues increasing. That the rain-water, and especially the first drops, 

 contain it abundantly, is seen by the deep color of the slips exposed to 

 its aspersion. In the stalls of stables, in which the air is moist and 

 ammoniacal, the slips do not change color, or do so very slowly as 

 compared with those placed in empty stables. Will this explain any 

 benefit phthisical patients were once supposed to derive from breathing 

 such air ? 



Dr. Heidenreich made a series of daily observations upon the rela- 

 tion of the amount of ozone to the nature of the prevailing diseases, 

 from March 16 to May 22. He found that a strong ozonic reaction 

 coincided with an exacerbation of the symptoms of catarrh and the 

 appearance of pulmonary phleginasias, while a diminution of these 

 took place when it was feeble. On the other hand, affections of serous 

 membranes, as the arachnoid, and of the synovial, as also various cuta- 

 neous affections, appeared during very feeble signs of the presence of 

 ozone. Rheumatic affections seemed connected rather with a large, 

 than a small amount, while pleuritis was as often met with in the one 

 case as the other. 



Dr. Faber (with other German observers) doubts the existence of 

 any connection between the development of ozone and the prevalence 

 of catarrhal affections. A year's observations, during 1848, failed to 

 confirm the accuracy of Schonbein's conclusions upon this point. He 

 found, too, the color both strong and weak, whether the barometer 

 was low or high, but perhaps oftener weak when it was high, and 

 strong when it was low. Cmcdee Annali., vol. 130, p. 155. 



