PROCEEDINGS. 
517 
On motion of Mr. Harkness, it was Voted that a committee of 
three be appointed by the Chair to draft suitable resolutions 
and present them at the first meeting of the next session. 
The Chair appointed Messrs. Harkness, Taylor, and Wood¬ 
ward. 
The following communications were presented: 
The Sphygmograph, by Mr. R. T. Edes. [The substance of 
this paper has been published under the title “A New Clinical 
Sphygmograph,” in the Journal of the American Medical Asso¬ 
ciation, August 18, 1888.] 
The Recent Mount Vernon, Ill., Tornado, by Mr. H. A. Hazen. 
[Abstract.] 
This tornado was unusually interesting, in that it possessed in a marked 
degree most of the characteristics of a typical tornado, and in that it oc¬ 
curred at a very early date (February 19) for this latitude. A chart was 
presented giving the distribution of the meteorological elements just pre¬ 
ceding the tornado, which occurred at about 4.50 p. m. (central). A low 
area had moved at a velocity of about thirty miles per hour from the north 
of Texas, and at 2 p. m. was central at the point of meeting of the bound¬ 
aries of Iowa, Missouri, and Illinois. About 300 miles to the southeast of 
this point, in the region of uniform and fresh southerly winds, with 
southerly upper currents, was a region of narrow width, but nearly 300 
miles long, in which a large number of very destructive storms raged. The 
earliest was at Houston, Missouri, and the latest at Russellville, Illinois. 
An approximate velocity of 70 miles per hour was determined. 
A little later another tornado started about 200 miles to the southeast 
of the first and with its path parallel to it. The destruction at Mt. Ver¬ 
non was very great; 35 people killed and over $500,000 in property 
destroyed. The following is a brief rSsutn^ of the characteristics of this 
tornado: 
1st. It occurred about 300 miles to the southeast of an area of low 
pressure and in a region of rather brisk uniform southerly winds. 
2d. The temperature was abnormally high for this region. 
3d. Its motion was about 70 miles per hour, while that of the low area 
was only 30. 
4th. There were intense electrical disturbances all along its path. 
5th. The upper currents in all this region continued from the south or 
from a southerly direction. 
6th. It seemed to be an independent formation suddenly thrust in upon 
the southeast border of the low area. 
