LXXXIV ROYAL SOCIETY OF CANADA 



Field Work. — During the season of 1907, the geographical positions 

 of fourteen stations were determined, five of these being in Yukon Terri- 

 tory, the renlainder in Ontario and Quebec. The longitude of Dawson 

 was determined from the station on the 141s.t meridian which had been 

 established the previous year, and the former was used as the initial 

 station for the other points in the Yukon ; these observations were made 

 by Messrs. F. A. McDiarmid and W. C. Jaques. Previous to this, Mr. 

 McDiarmid, in conjunction with Mr, Smith, of the U. S. Coast and 

 Geodetic Survey, had laid down the azimuth of the initial line for the 

 141st meridian; an extension of this line is to form the northern part of 

 the boundary between Yukon and Alaska. During the present season it 

 is proposed to establish several points along the 49th parallel, and a 

 number in the Maritime Provinces ; the work is now under way. 



A new method of making meridian transit observations has been 

 adopted by the observatory. An investigation, undertaken by E. ^I. 

 Stewart, has shown the method ordinarily used in this country to be 

 defective in that it does not furnish a sufficiently strong determination 

 of the azimuth error of the instrument. This can be partially remedied 

 by the observation of a proportionately larger number of north stars, 

 but this is limited by the scarcity of suitable standard stars in the 

 northern heavens. The accuracy is increased by observing each star 

 twice, both before and after it has crossed the meridian, reversing the 

 instrument between the observations. These two changes, combined 

 with a selection of south stars as near the zenith as they can conveniently 

 be observed, result in a considerable increase in the accuracy attainable. 

 All observations are now taken with the registering micrometer; alter- 

 ations have been made in the automatic registering apparatus, for the 

 purpose of giving thel tnvo records mentioned above. 



Time Service. — The time service to the Government Buildings in 

 the city has been continued as heretofore, and some extensions and im- 

 provements made. Besides a system of secondary clocks in the City Post 

 Office, the six foot electric tower dial in that building has been in- 

 stalled and an attachment added by which it controls its own illumina- 

 tion; this is so arranged that the duration and time of illumination may 

 be easily altered from time to time as required. 



The wires running from the observatory to the city, for synchroniz- 

 ing secondary master-clocks, are rented from the Bell Telephone Com- 

 pany. As they necessarily nm in cables with many other wires, and pass 

 through the racks in the Company's exchange, they arc liable to be in- 

 volved in inadvertent derangement by the constant repairs and altera- 

 tions inseparable from a telephone system. With the system of syn- 

 chronization in use, no harm can result from the opening of the con- 



