proceedings: philosophical society 297 



For the gas dielectric the greater problem is the mechanical one, while 

 for the solid dielectric the question of anomalies is the more serious. 

 The paper was discussed by Mr. Gray with reference to values of 

 capacity at different voltages. 



The Secretary read communications inviting members of the Society 

 to attend the meeting of the Washington Academy of Sciences on 

 January 30 at the Cosmos Club to hear an illustrated address, Some 

 observations of the volcano Kilauea in action, by Dr. A. L. Day; and also 

 to attend a meeting on January 27, at the Bureau of Standards to hear 

 Professor Magie of Princeton on Our conception of energy. 



The 719th meeting was held on February 1, 1913, at the Cosmos Club, 

 with President Abbot in the chair and 16 persons present. The minutes 

 of the 718th meeting were read and approved. 



By invitation Mr. Alfred Lotka presented an illustrated paper on 

 A natural population norm. Pubhshed in full in this Journal, 3: 241, 

 289. 1913. The paper was discussed by Messrs. Burgess, Wolff, 

 Burrows, and Abbot. 



Under informal communications Mr. Abbot spoke of the recent work 

 conducted and the results obtained with the pyrheliometer showing 

 that a standard scale of pyrheliometry is now well established. Mr. 

 Humphreys offered an explanation of the present mild winter in the 

 District of Columbia and neighboring region in that the high pressure 

 center usually located in the East Atlantic off Gibraltar has shifted of 

 late to the neighborhood of the Bermudas and in consequence we 

 receive with southerly winds the mild marine climate. No cause for the 

 shift could be assigned. Mr. Kimball spoke of the remarkable dimi- 

 nution since June 10, 1912, of the Solar radiation as measured at the 

 surface of the Earth; during the six months to December the radiation 

 was but 83 per cent of what it had been in previous years at Mt. Weather. 

 There appears to be some relation with the eruption of the Volcano 

 Katmai in Alaska of June 6, 1912. A study of the results promises 

 to give interesting light on the circulation of the atmosphere. 



The 720th meeting was held on February 15, 1913, at the Cosmos 

 Club. President Abbot in the chair; 50 persons present. 



The evening was devoted to the address of the retiring President, Mr. 

 E. B. Rosa, on The function of research in the regulation of natural jnonop- 

 olies. Published in full in this Journal, 3 : 201. 1913. 



The 721st meeting was held on March 1, 1913 at the Cosmos Club. 

 This meeting was held conjointly with the Washington Academy of 

 Sciences. President Tittmann, of the Academy, presided. There were 

 about 200 persons present. 



The Right Honorable James Bryce, 0.!M., British Ambassador to 

 the United States, gave an address on The physical aspects of Australia 

 and New Zealand. The islands of New Zealand are very mountainous 

 and the scenery of great beauty. The climate is generally moist. A 



