350 ADDENDA. 



have been very interesting. I found, as far as I could make de- 

 ductions from a single set of carefully-made observations, that the 

 ozone is manufactured between the tropics. I invariably found 

 the ozone most abundant in the winds that blow north and south 

 of the trades from the equator. In the winds from the pole there 

 was but little ozone." 



Not much is known of ozone. Whence comes it, or how is 

 it elaborated? Some maintain that it is generated by electrical 

 discharges and explosions. If so, then the equatorial calms and 

 cloud ring would fulfill the conditions of the great laboratory of 

 nature for this subtilty» A regular and systematic series of ozo- 

 nometrical observations on board ships at sea might throw much 

 light upon the circulation of the atmosphere by converting the 

 ozone into tallies for the winds. It is, therefore, to be desired, 

 that those who are co-operating with me, by making observations 

 to assist in the investigation of the phenomena of winds and sea for 

 the benefit of navigation, will extend their field of research by di- 

 rectino; their attention to the ozonometer also. 



When I first received the account of Lieutenant Jansen's ob- 

 servations, which so clearly marked the excessive presence of ozone 

 in winds coming from the equator as compared with winds coming 

 from the poles, I had not seen any account of either Pegado's or 

 Eogers's observations, and fell, therefore, into the error, perhaps, 

 of attaching, in an addendum to the sixth edition of this work, 

 undue importance to a single series of -observations. The results 

 of the observations, now that they begin to multiply at sea and on 

 land, and in different parts of the world, appear to differ so much 

 from each other in certain aspects, that it will require many series 

 of carefully-made observatl'ins before we can reasonably hope to 

 generalize boldly and with confidence touching this new substance. 



This invisible substance, like magnetism and sea-dust, is a gos- 

 samer-like clew,- intended to guide us through the mazes of the air, 

 and along the paths of the wind. But, because it is invisible, im- 

 palpable, and fine, we want so much the more to trace it up by 

 the foot-prints it makes, and ascertain the secrets of its chambers.* 



* Dr. Breed, of Washington, has very kindly furnished me with the following rec- 

 ipe for ozone paper : 



