164 MINUTES. 



[May 4 



Stated Meeting May 4, ipod. 

 President Smith in the Chair. 



Dr. David L. Edsall, a newly elected member, was presented to 

 the Chair and took his seat in the Society. 



Letters accepting membership were read from: 



Hon. Joseph Hodges Choate, New York. 



John W. Harshberger, Ph.D., Philadelphia. 



William Francis Hillebrand, Ph.D., Washington. 



Charles Rockwell Lanman, LL.D., Cambridge, Mass. 



Ernest Fox Nichols, D.Sc, New York City. 



Hon. Elihu Root, LL.D., Washington. 



Thomas Day Seymour, LL.D., New Haven, Conn. 



Edward Bradford Titchener, M.A., Ithaca, New York. 



Otto Hilgard Tittmann, Washington. 



Dr. Hendrik Antoon Lorentz, Leyden. 



The decease was announced of Mr. Edward Floyd deLancey, 

 at Spining, N. Y., on April 7, 1905, set. 83. 



The following letter was read from Prof. George Davidson, 

 of San Francisco, in relation to 



The San Francisco Earthquake of April 18, 1906. 



In the matter of the earthquake of April 18, while you were celebrating 

 the two hundredth anniversary of the birth of Benjamin Franklin, I beg 

 to give the following memorandum as a matter of record : 



The shock occurred at 5^ 12"" 00^ A. M., Pacific standard time. The 

 first movement was short and sharp, north and south, and of slight amplitude 

 at my home 300 feet above the Bay; it changed to movements east and west 

 and every direction, with very quick shocks (say four per second), of small 

 amplitude and complex, for 60 seconds ; when a slight but gradual weakening 

 was apparent for 30 seconds more. After this the vibrations weakened 

 gradually to quietness in another 60 seconds. The whole movements occupied 

 2™ 30^ I began my count with the first shock, and soon afterwards timed 

 the event with my chronometer watch. 



The sensation suggested the sharp vicious action of a terrier seizing and 

 shaking a rat. 



There was a slight shock at 5^ 17™ (approx.) and another at S^ 29™ 

 (approx.) and some later ones of no consequence. 



In other parts of the city and the adjoining districts the amplitude of the 

 shocks has been much greater, if we judge by results; and yet very unequal. 



The general indications point to this statement: That the greatest ampli- 



