The first continuously recording photographic seismograph station in North America began operation in September 1897 in Toronto. The first Canadian seismogram had been recorded in Montréal on March 23, 1897. Stations at Victoria (1898), Ottawa (1906), Saint Boniface (1910), Halifax (1915), Saskatoon (1915), and Resolute (1950) were established to record teleseisms; those at Ste-Anne-de-la-Pocatière (1925), Shawinigan Falls (1927), and Seven Falls (1927) to record local earthquakes in part of the St. Lawrence Valley. The station at Kirkland Lake (1939) monitored rockbursts in the adjacent gold mines. The original low-gain seismographs at most of these stations were replaced by instruments more sensitive to local earthquakes as interest in studying Canadian seismicity grew.
These changes in instrumentation for the nine permanent seismograph stations installed in eastern and central Canada prior to 1955 are tabulated with supporting references. All but Ottawa and Halifax are now closed. A relatively recent station at La Pocatière is very close to the original Ste-Anne site. An outline of the development of the Canadian seismograph network prior to 1955 precedes the tables. Arrival times at some seismograph stations in the northeastern United States had been used to locate early Canadian earthquakes. Instrumentation with operating dates for the following six stations established before 1940 are also tabulated with references: Cambridge (1908), Fordham (1910), Weston (1930), East Machias (1932), Harvard (1933) and Williamstown (1937).