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THE Observatory at Ottawa to-day is an evolution of the astronomic work inaugurated in 1885 in connection with the

Railway Belt in British Columbia.

British Columbia entered Confederation, became part of the Dominion of Canada, on July 20, 1871.

One of the conditions upon which British Columbia entered the Dominion was the speedy construction of a trans-continental railway, and in this connection, by the Imperial Order in Council of the 16th May, 1871, British Columbia conveyed in trust of her Crown Lands to the Dominion ". . . . not to exceed twenty miles on each side of the said line" (railway). These twenty miles on each side of the railway are known as the Railway Belt, and became Dominion Lands, to be administered by the Department of the Interior, and furthermore, to be correlated with the Dominion Lands survey system of the Northwest, a system based on geographic co-ordinates.

The mountainous character of British Columbia precluded projecting and running standard base-lines and meridians, as had

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been done over the wide expanse of prairie from Winnipeg to Calgary and Edmonton. However, another method was available, and that was to establish a number of astronomic stations accurately determined in latitude and longitude along the railway line, and furthermore to make a very accurate azimuth survey of the railway connecting the survey with the astronomic stations. With these data it was thus possible to compute with precision the position on the earth, that is, in latitude and longitude, of every point of the railway, and hence the position it would occupy were the rectangular net of Dominion Lands Survey spread over the Railway Belt, becomes known. The distance involved in this survey was 512 miles, extending from Port Moody, the original Pacific terminus, to the summit of the Rocky Mountains.

In 1885 there was no Vancouver; it subsequently became the terminus. Accordingly in the spring of 1885 (the last spike of the railway was driven at Craigellachie on November 7, 1885). the Surveyor General, E. Deville, issued instructions to two astronomers, T. Drummond and Otto Klotz, to make the astronomic observations, and to W. Ogilvie to make the azimuth survey. It may be noted that the official use of the word astronomer by the Department was for the first time made in the above case.

The beginning was made from the Pacific end of the line, and the writer had charge of the astronomic work. The nearest well-determined point was Seattle, the astronomic position being determined by the U. S. Coast and Geodetic Survey, its longitude being based on Greenwich. Hence Seattle became the initial point for our longitudes, and from it were established Victoria. and Kamloops, the latter becoming in turn the basal longitude station, to which were referred Port Moody, Revelstoke, Field and other stations as far east as Winnipeg.

The astronomic equipment consisted of two Troughton and Simms portable transits, Fo. 1, and Fo. 2, each of 21⁄2-inch aperture and 28 inches focal length, previously used on the 49th parallel Boundary Survey of 1872-1874; two sidereal box chronometers by Dent and Frodsham, respectively; two pocket chronometers; one zenith telescope for latitude work, and two standard registers

of the Western Union Telegraph Company, on the tapes of which the clock signals, sent by hand, were recorded. In 1885, besides Occupying Seattle, the positions of Victoria, Port Moody and Kamloops were determined, and the azimuth survey carried from Port Moody to Farwell, now Revelstoke. In the following year Revelstoke, Field, Calgary and Winnipeg were occupied.

At Calgary a connection was made with the 5th Initial Meridian, and at Winnipeg subsequently with the Principal Meridian and with longitudes from the east for a comparison with the longitude brought across the continent through the United States. and eastward again via Seattle and British Columbia.

The success of these two years of astronomic work in connection with the accurate determination of geographic positions for the Department of the Interior gave astronomic work a permanent footing in the Technical Branch under the Surveyor General, E. Deville, and this led to an extension of its application to a wider field, not only within the vast area of Dominion Lands in the Northwest, but also in other parts of Canada for cartographical and other purposes.

It was essential that the longitude of Winnipeg be well established by connection with the east (Harvard), as it was to serve as a base station. The adopted longitude of Winnipeg rested upon a rather unsatisfactory determination of West Lynne from Dearborn Observatory, Chicago. By linear measure from West Lynne along the 49th parallel, the international boundary line, the longitude of the Principal Meridian was established, and by triangulation from the latter to Winnipeg the longitude of Winnipeg was found.

On February 10, 1887, the Surveyor General, E. Deville, submits to the Deputy Minister a memorandum suggesting the establishment of an observatory at Ottawa in connection with the longitude work in the west. This was approved by the then Minister, the Hon. Thos. White, but nothing was done.

In March, 1887, W. F. King and the writer officially visited Boston, Cambridge, New York and Washington, with the object* of inspecting, subsequently to purchase, a transit for the proposed

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