REPORT OF KXECUTIVE COMMITTKE. 73 



will be made of any possible previous instances in which terrestrial 

 eruptions were accompanied by magnetic disturbances. 



The average time of the beginning of the magnetic dis- 

 turbance on May 8, 1902, was y*" 54.1'" a. ni., St. Pierre local 

 mean time. According to Heilprin, the hands of the clock on 

 the town hospital were found stopped at 7" 52'". 



As it is not known how accurately the clock kept local mean time, 

 it is probable that the time as given by the magnetic disturbance is 

 the most accurate determination of the time of the eruption to be 

 had. 



Investigation III. Compilation, discussion, and publication of the existing 

 data concerning the variations of the earth's magnetism other than the 

 secular variation already provided for in Investigation I, and the perturba- 

 tions of the earth's magnetism. 



In connection with Investigation I, it has been found necessary, 

 as related in that section, to make some preliminary studies on the 

 geographical distribution of the corrections due to the diurnal vari- 

 ation of the magnetic elements. More than this it has not been 

 deemed wise to attempt at present, until the correspondence with 

 institutions and persons has been completed. Some preliminary 

 negotiations have been entered into with Prof. Adolf Schmidt, in 

 charge of the magnetic observatory at Potsdam, Germany, regarding 

 the di.scussion of recent magnetic storms, to be conducted under 

 his direction, with the aid of computers employed by the department. 



MISCEIvLANEOUS. 



In order that the department may have full knowledge of material 

 and investigations, so as to avoid duplication and reveal deficiencies, 

 a circular has been prepared for forwarding to persons and institutions 

 engaged in work relating to the department. A card catalogue is 

 furthermore being kept of all publications and data obtained, for 

 ready reference by the members working in the department and for 

 rapidly replying to calls for information from outside. The depart- 

 ment is thus enabled to fill an important need in magnetic research. 



The department was represented by the director at the following 

 congresses, viz : Eighth International Geographic Congress, Inter- 

 national Electrical Congress (St. Eouis), and International Congress 

 of Science and Arts (St. Louis). At each of these congresses he 

 presented, upon special invitation, papers relating to the earth's 



