RECORDS 109 



national Congress of Zoologists, and to appoint Professor E. B. 

 Wilson delegate. That the meetings of the next year would be 

 held at the rooms of the Chemists' Club, io8 West 55th Street. 

 That the delegates to the Scientific Alliance would be President 

 Woodward, cx-officio, Mr. Cox, and Professor H. F. Osborn. 



Richard E. Dodge, 

 Re CO nil Jig Sec re tan ' . 



SECTION OF ASTRONOMY, PHYSICS AND 

 CHEMISTRY. 



March 4, 1901. 



Section met at 8.25 P. M., Professor J. K. Rees presiding. 



The minutes of the last meeting of Section were read and ap- 

 proved. 



The following program was offered : 



R. S. Woodward and J. W. Miller, Jr., The Elastic 

 Properties of Helical Springs. 



F. L. Tufts, A Photographic Study of the Air Move- 

 ments NEAR THE ]\IOUTH OF AN OrGAN PlPE. 



Before the program of the evening, an election of officers of 

 the Section was held, resulting in the election of Prof. William 

 Hallock as Chairman and- Dr. F. L. Tufts as Secretary of the 

 Section for the ensuing year. 



Summary of Papers. 



In his paper, Dr. Tufts described preliminar\^ experiments 

 in which he applied the " method of strice " similar to that used 

 by Toepler, Boys, Wood, and others, to the study of the vibra- 

 tions within an organ pipe. The pipe used had sides made of 

 plane parallel glass plates. The tongue of air at the mouth of 

 the pipe was made visible by using air mixed with alcohol vapor, 

 which changed its optical density. The vibrations and air cur- 

 rents within the pipe were made visible by the introduction into 

 the pipe of small jets of illuminating gas. The intermittent il- 

 lumination used was the spark between magnesium ribbons 

 from an induction coil. It was found quite easy to adjust the 



