Academy of Science. 23 



.56, in September. The day records present their highest mean, 3.20, in May, and 

 their lowest, .76, in September. These minimum results are the lowest obtained in 

 the State. Mr. Long has prepared his own iodized paper, and his observations have 

 been conducted in the city of Lawrence, near the foot of University Hill, upon a 

 street largely populated by colored people. These records are now under charge of 

 Mr. W. H. Carruth, who has transferred his base of observation to a much higher 

 locality, nearly upon the same level with the University, where he has obtained quite 

 startling results. For the month of May, for example, he has obtained a maximum 

 of 10 (highest on the scale) for both day and night records, with a mean for the 

 month of 5.30 for the day and 5.55 for the night. The records of the station at 

 Ellinwood have been conducted by Mr. B. B. Smyth, beginning with June, 1876. 

 Thej^ are characterized throughout by a uniformly high average. The night records 

 almost invariably far exceed those of the day. The highest mean of the night 

 records is reached in March, 1877, 5.85 ; the lowest in February, 1877, 3.65. The 

 day records attain their highest mean in April, 1877, 5.37 ; their lowest in August, 

 1876, 2.27. These results would seem to indicate a greater quantity of ozone in 

 the higher regions of Western Kansas than in that of its low^er eastern border. 

 The observations at Washburn College, Topeka, have been under the charge of 

 Prof. John B. Dunbar. They were begun in April, 1876, and are cliie% remark- 

 able for their great uniformity throughout the year, and for the alternate superi- 

 ority of the day and night records. I have never in my experience seen records 

 varying so little in their results. The highest mean for the night is in June, 1876, 

 3.08; the lowest in October, 1876, .97. For the day records the highest mean is 

 reached in May, 1876, and February, 1877, 2.18 ; the lowest iu November, 1876, 1.18. 

 Among the most interesting results obtained were those by Dr. A. H. Thompson, of 

 the city of Topeka. Dr. Thompson's place of observation was adjacent to the 

 A., T. & S. F. Railway depot, with the bulk of the city lying south and west and 

 north. The prevailing winds of this locality thus brought foul air from almost 

 every direction, and, as a natural result, scarcely a trace of ozone could be detected. 

 This result was due both to the presence of organic impurities with which the 

 atmosphere was loaded, and also to the sulphurous acids in the coal smoke of the 

 railway which would instantly destroy whatever color might have been imparted 

 to the test paper. This powerful bleaching efTect of sulphurous acid may be 

 easil}^ shown experimentally by holding a test paper, turned a deep blue by the 

 action of ozone, near a freshly lighted sulphur match, when the color will instantly 

 vanish. Observations taken in other portions of the city by both Dr. Thompson 

 and Prof. Thomas, furnish somewhat higher results. The records of Manhattan 

 under my own supervision show for the past year somewhat lower results than 

 those obtained in 1874-5. Upon examining the diagram the somewhat singular 

 fact is noticed, that from January to June the night records exceed the day ; and 

 from June to December the day records exceed the night in about equal amounts 

 in each case. The highest mean for the night observations is reached in March, 

 5.65; the lowest in August, 1.10. For the day records the highest mean appears 

 in December, 5.03 ; the lowest in August, 1.30. It was the intention in organizing 

 these series of observations, to study and record with great care all phenomena in 

 connection with ozone which might in any manner assist us in ascertaining its 

 relations, if any exist, to health and disease. Observers were requested to spe- 

 cially notice and record "any apparent connection between the abundance or 

 deficiency of ozone, and the prevalence or absence of any given diseases ; or any 

 influence observed in modifying the types of such diseases." But it is quite need- 

 less to state that the failure of promised co-operation has prevented any investiga- 



