1876] •^^^ [Blasius. 



average direction of their flight? We mix tilings that do not belong to- 

 gether and arrive at best at indefinite, vague and unreliable results. Tliis 

 evidently has happened in determining the direction of the axis of a sup- 

 posed revolving column of air. 



The discrepant views of the celebrated meteorologists above mentioned, 

 will all harmonize if considered from the standpoint indicated in my recent 

 work. The supposed revolving column of air is seen from my standpoint 

 as the obliquely rising equatorial, or warm current ; its direction always 

 inclines towards the north, or colder region. It thus coincides with the 

 position of the axis of the supposed revolving column; in a north-east storm 

 it is inclined forward, in a south-east storm backward, in a local storm it 

 is vertical. The method of averaging will lead to the first result if the 

 cases subjected to investigation belong all or in the majority to north- east 

 storms ; it will lead to the second result if the cases subjected to investiga- 

 tion belong in the majority to south-east storms ; it will bring no result, or 

 make the axis vertical if the cases or data subjected contain a number of 

 both kinds in equal proportions. 



Mr. Blodget remarked that there were very striking and 



valuable suggestions in Mr. Blasius' paper. 



He thought that it was true that the influence of the Signal Service was in 

 danger of being weakened by its j)ersistent observations of only three hours 

 in the day. Storms require observation continuously during their course. 

 He agreed with Mr. Blasius, also, in accounting of inferior values other 

 elements of the discussion of storms, those areas of low and high barometer 

 which almost exclusively occupy the S.S. maps. He described the remark- 

 able storms of 1873, accompanied with disastrous floods. They were not 

 parts of a common storm usual to the Temperate Zone, raining from the 

 lower portions of the atmosphere coming from the Gulf; but on the con- 

 trary, they were numerous local furious downpours from a hot supersat- 

 urated upper air coming from some more distant, unknown region in the 

 South. They had the characteristics of tropical storms, and w^ere so local, 

 that in some instances a distance of only twenty miles sufficed to distinguish 

 a flooded locality from one on which no rain fell. Mr. Blodget added, 

 that, having in former years participated in the discussion of Espy, Redfield 

 and Hare, he could meet the vertical theory with an expressed conviction 

 of the impossibility, quite demonstrable, that a large storm should rotate 

 upon the rough surface of the earth; although it must of course remain true 

 that any disturbance in fluids has a tendency to set up vertical movements. 

 The vast obstructive friction of the face of a country in the case of great 

 air movements must always prevent any rotation over wide areas. Local 

 tornadoes may produce small whirlwinds, but a Redfield cyclone is a phys- 

 ical impossibility. He had found in Mr. Blasius' book more of a true expla- 

 nation of the origin and progress of storms than elsewhere. "While Mr. 

 Blasius had proposed the Signal Service system in 1851, he had himself 

 used the telegraph in the Summer of 1852 for two months; and his charts 



