32 Trans. Acad. Sci. of St. Louis. 



In a plant now being placed upon the new Physics build- 

 ino^ at Washington University, the standard pressure tank 

 has a volume of about 240 liters. Some of the gauges which 

 open into it will show a decrease and others an increase 

 of pressure. It is thought that the tank will be large enough 

 to insure a practical elimination of reactions of the gauges 

 upon each other. More than 3,000 feet of pipe is used in 

 connecting the various pressure collectors with their respec- 

 tive guages. A photograph of these gauges and other indi- 

 cating devices, will show the simultaneous values of wind 

 pressures at various points on the building, the wind velocity 

 in free air, and the wind direction with respect to the sides 

 of the building. 



If a plant of this kind could be established on a high 

 office building, some very valuable information could be 

 obtained. 



IsmedL May 31,1906. 



