THIRTEENTH ANNUAL REPORT 23 



trained individual to have actual charge of silk culture and its 

 propaganda in the Philippines becomes more apparent as time 

 goes on. 



CHEMICAL LABORATORY 



During the last school year Dr. Harry D. Gibbs, chief of the 

 division of organic chemistry, and Mr. Albert H. Wells and 

 Mr. F. Agcaoili, assistants in the division, were detailed for part 

 of their time to the department of chemistry of the University of 

 the Philippines, and Dr. A. P. West, an assistant in the division 

 of general, inorganic, and physical chemistry, was detailed to 

 give all of his time to the University. Mr. Albert E. W. King, 

 an assistant in the latter division, has given a course in testing 

 cement to students of the College of Engineering. The assist- 

 ance has been given to the University at considerable sacri- 

 fice and interruption of the continuity of our work, and all 

 with the exception of the course in cement testing had to be 

 discontinued on account of resignations and the depletion of 

 our staff. 



Physical research. — Since my last report the work on the 

 relation between the electrical and meteorological conditions 

 of the atmosphere has been continued under the direction of 

 Dr. J. R. Wright, the scope of the work being extended to in- 

 clude several additional correlated factors. Observations on 

 the radium-emanation content of the atmosphere of Manila have 

 been continued with the view of determining both the annual 

 and diurnal variation with meteorological conditions. During 

 April and May of the two preceding years an extensive series 

 of observations has been taken on the top of Mount Pauai, Ben- 

 guet subprovince, in order to determine the variation of the 

 radium-emanation content with altitude. Simultaneously with 

 the above investigation, observations have been taken on the 

 amount of radium and thorium emanation in the atmosphere by 

 the active-deposit method, the chief object of which is to deter- 

 mine the diurnal variation and its relation to the humidity, 

 barometric pressure, and other meteorological factors. Work 

 has also been started on the following problems: (1) Determina- 

 tion of the ionization of the atmosphere by Ebert's method, (2) 

 determination of the rate of production of ions in a closed vessel 

 due to the penetrating radiation from the radioactive substances 

 in the atmosphere and the earth's crust, (3) determination of 

 the diurnal variation of the potential gradient at the surface of 

 the earth, and (4) the absolute value of the intensity of the rays 

 from the sun. 



