Canadian Coast Guard
<% else %>A History of the Canadian Coast Guard and Marine Services
by Thomas E. Appleton
Tidal and Current Survey
Once the business of charting Canadian waters was fairly under way, the Department turned its attention to the estimation of current and the prediction of tides, until then largely a matter of local observation.
About the only work done previously in this connection had been the calculation, by Admiralty surveyors, of the tidal constants known as "the time of high water, full and change", which information was recorded on the charts. In 1889, Andrew R. Gordon, not long returned from his successful survey of the Hudson Bay route, was asked to report on the cost of setting up a tide and current survey. In the best administrative tradition, Gordon took note of such facilities as existed at the time, reviewed their possibilities, and recommended a course of action, complete with estimated costs. He found that there had been a self-registering tide gauge in Halifax Dockyard, but that it had fallen into disuse and that the system of prediction:
". . . is not only faulty in theory, but is in practise often erroneous to a very considerable degree."
Observing further that the:
". . . loss during the present year of the SS Montreal and HMS Lily, whether in each case actually due to the action of unknown currents or not, certainly indicates the desirability of giving to navigators all the information in regard to currents affecting their ships. . ."
Gordon went on to recommend a scheme for the establishment of scientific observations from a number of widely separated stations over a period of ten years, leading to the prediction of annual tide tables. This was an expensive matter in terms of departmental budgets of the day, and Gordon, who by this time had become experienced in the ways of government reports, added to his ten years estimate, of some two hundred thousand dollars, the final sweetener " . . . or one half the cost of a single first-class freight steamer" per year.
The Tidal and Current survey was established, as recommended, and in due course passed to the administration of the Hydrographic Service, and the tide tables were produced along with other Canadian navigational references.
In these days of automatic recording instruments, the acquisition of scientific statistics of lake and sea remains a lengthy and expensive procedure. In 1889, when so such instruments existed, the only way to get information on tides and currents was to anchor a ship on the spot and find out. Looking back on this first tidal and current survey, who knows what lonely and dreary watches were spent in tending the hand lead from the decks of a heaving schooner or small steamer, rolling incessantly between wind and tide, in the open spaces of Canadian waters. Surveys of this kind, carried out with meticulous observation within the limits of primitive instruments, were the very stuff of marine science, in which this country now takes a leading part.
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