ADDENDA. 



Page 147, ^ 394. 



ScHONBEiN, a few years ago, discovered ozone in tlie atmos- 

 pliere, and since that, thougli chemists are not agreed as to what 

 this new substance is — if it be a new substance — or how, or where, 

 in the laboratories of nature, it is generated, it has been used by 

 meteorologists as an implement or means for carrying on their 

 observations. 



The indefatigable Dr. Pegado, in his capacity as Director of the 

 Meteorological Observatory of the Polytechnic School of Portugal, 

 has introduced into his meteorological journal a column for reg- 

 ular ozonometrical observations. He has the usual scale of colors, 

 and makes two observations a day. In order to make an obser- 

 vation, the ozone paper is exposed to the air for 12 hours, and 

 then, according to the depth of the color which the paper has as- 

 sumed, the relative abundance of ozone is judged of. 



The doctor commenced these observations in July, 1855 ; and, 

 according to the meteorological annals of the Polytechnic School 

 from July to November of that year, the quantity of ozone in the 

 atmosphere appears to be directly as the moisture, and inversely 

 as the pressure, without regard to the direction of the winds. 



In Massachusetts, according to the observations of Professor 

 W. B. Eogers for six weeks in winter,* ozone is most abundant in 

 northwestwardly winds ; least so in winds having southing or 

 easting in them. 



My friend Jansen, of the Dutch Navy, made a series of obser- 

 vations with ozone paper all the way from England to Australia. 

 He was on board the " Royal Charter" in the spring of 1856, 

 when she made the unprecedented run of 59| days to Australia. 

 His observations were made on board that vessel, and, in giving 

 me an account of the voyage on his arrival at Melbourne, he says : 



" I forgot to mention my observations with ozone paper. They 



* See Transactions Soc. Nat. History of Boston, v. 319. 



