HORTICULTURAL SOCIETY. 105 



still falling in Florida, having now reached 30° in the central 

 part of the peninsula. 



Our next chart represents the storm at its maximum. This is 

 the morning of the tenth. The low barometer has now reached 

 the mouth of the St. Lawrence, and the zero line extends from 

 Utah, through i^ew Mexico, Texas, Arkansas, Mississippi, Ala- 

 bama, Georgia, jSTorth Carolina, and Virginia, and the line of 

 30° crosses Florida as far south as Punta Eassa. 



The disastrous results of this storm, in the extreme south es- 

 pecially, are fresh in your memories. It is said that no such 

 cold has occurred in Florida, as demonstrated by its effect on 

 tender vegetation, since 1835, when they unquestionably had 

 similar atmospheric conditions as the predisposing cause. 



But the unusual character of this storm was manifested solely 

 by its severity in the South. It has frequently been colder here, 

 or even where I live, in the last half century, than on this occa- 

 sion. Indeed, only two weeks later we were warned to ''hoist 

 cold wave flag," and notified that you were having several de- 

 grees lower temperature here than you had during the previous 

 storm, but we did not realize its increased severity, while in 

 Florida they were scarcely disturbed, the change from nominal 

 temperature being hardly noticeable. On consulting the charts 

 for this second storm, we discovered that the low barometer, the 

 disturbing cause, had originated very near the location . of the 

 preceding storm, viz., in Colorado, but, instead of the unusual 

 route taken by the first, had followed the nominal cause, in an 

 almost direct route toward the Gulf of St. Lawrence, and hence 

 the high barometer and cold wave were only invited as far 

 south as the line of the preceding low area. 



Mr. Pearse. I would like to inquire if cyclones are not liable 

 to occur in certain locations; that is in valleys and among 

 hills, as they usually commence, I understand, on high land? 



Prof. Eagan. You have reference to tornadoes. They are sup- 

 posed to be engendered by countercurrents; virtually because 

 of the effects of heat. We do not know exactly what causes 

 them, unless they are due to this difference in the atmospheric 

 pressure. 



Mr. Pearse. My friend Sias lives in a town were they have 

 had several tornadoes. I lived there for many years, and I 

 studied this subject carefully. Eochester is situated in a low 

 valley, surrounded by a number of hills. The valleys come to- 

 gether, and I have noticed they come down through those 



Vol. IV.— 14. 



