APPENDIX B LXIII 



Meridian Observations. 



Observations with the meridian circle were made on 126 nights. 

 On 101 nights the work was devoted to the Hst of latitude stars which 

 has been under observation for several years; the number of obser- 

 vations obtained was approximately 2,000 for right ascension and 

 1,800 for declination. Two observers were engaged throughout the 

 year, and two others for shorter periods. 



The regular programme of astronomical field-work comprised 

 the determination of the latitudes and longitudes of fifteen stations, 

 seven of these being in British Columbia, and eight in Quebec. Kam- 

 loops, one of the stations in British Columbia, was used as a longitude 

 base for the remaining six, it being first determined from Field, B.C., 

 the previous base station. 



The longitudes of the stations in Quebec were determined from 

 Ottawa. Three-inch Cooke transits, with registering micrometers 

 and latitude levels, were used for the field observations; personal 

 equations were determined as usual. 



Besides these stations the longitudes of four others in the Province 

 of Quebec, where no telegraph line was available, were determined 

 by wireless telegraphy. For this purpose the time signals sent out 

 by the U.S. wireless station at Arlington, Va., were utilized as a means 

 of comparison between the observer's chronometer and the Obser- 

 vatory sidereal clock, thus replacing the usual "arbitrary signals" 

 transmi'îted over the telegraph line for the same purpose. To effect 

 the comparison, a break-circuit chronometer, rated to gain about 

 ten minutes per day, was caused by a suitable arrangement to beat 

 in the telephones of the wireless receiving set, at the same time that the 

 wireless time-signals were being received ; by noting the times at which 

 coincidences occurred it was found possible to make comparisons to 

 within about -01 second. This being done at both the field station 

 and the Observatory, a direct comparison of clocks was efifected, 

 independent altogether of the accuracy of the Arlington signals. The 

 transportation in the field was effected by canoe; the receiving 'aerials 

 were erected on trees, ground connections being made in running 

 water wherever possible. The results indicate that the accuracy 

 of such longitude determinations may be expected to be practically 

 the same as those determined by wire. The latitudes of these stations 

 were also observed. The telescope used was a portable broken-type 

 transit by Heyde, fitted with registering micrometer and latitude 

 level. 



The time-service has been maintained as in previous years. 

 About 325 electrically driven clocks are operated in the various 



