Enthusiasm for Second Empire, fanned by federal allegiance to the style, was also manifest in public architecture at the provincial and municipal levels, in commercial and religious buildings and in the homes of wealthy fashion-conscious urban residents. Important design features such as pavilions and rich sculptural decoration were often lost in the diffusion of the style but the visually alive mansard roof remained a characteristic trait. During the 1870s “modernization” in fact became a craze, frequently being superimposed on buildings whose main stylistic roots lay elsewhere. In central Canada and particularly in Ontario, mansard roofs were covered with variously cut and colored slates.
Slate roofs were also a basic element in the Canadian treatment of the High Victorian Gothic style which emerged in the second half of the 19th-century. Abandoning the rational structuralism which dominated earlier phases of the Gothic style, architects embraced greater freedom of form with exuberant visual effects. In the execution of the irregular silhouettes, vertical thrust and colour accents that distinguished this free interpretation of the Gothic Revival, roof form and covering played an essential role. University College, Toronto (1856-59) “one of the first great High Victorian Gothic Buildings in Canada,”4В was capped by a banded polychromatic slate roof. A River elevation of the Parliament Buildings. The fashion was quickly assimilated by religious and domestic architecture creating a wider market for slate. The consumption of slate in Canada peaked in 1889 just before the influence of the High Victorian Gothic began to fade in the 1890s.
The principal periods for the popularity of slate roofing in Canada can be identified precisely by a review of the annual values of locally produced and imported roofing slate that appear in the reports of the Division of Mineral Statistics and Mining of the Geological Survey of Canada and the Tables of the Trade and Navigation of the Dominion of Canada. Canadian slate statistics, Which begin only in 1886, are slightly skewed by the inclusion of school blackboard slates in production figures from 1886 to 1896. By ascertaining the value of school slates from other sources, however, it has been possible to isolate the value of roofing slate production.
Quantities of imported and Canadian replace roof slate that would provide a more accurate index of use are not recorded in comparable units before 1900. Though Canadian production is initially recorded in tons, an 1889 Geological Survey report stated that the New Rockland Slate Quarry, the only quarry in operation that year, produced 400 squares of roofing slate. Added to the import of 8417 squares of American slate, Canadian consumption in 1889 thus attained 34 817 squares.
Between 1906 and 1914 when values again rose Canadians annually used between 20 000 and 22 000 squares of slate. About a third of this quantity was used from 1928 to 1930, although the total value or price of slate exceeded pre-war figures. Both yearly values and quantities of roofing slate thus reveal that the popularity of slate roofing in Canada reached its zenith in the period from 1886 to 1894. So great was the demand for slate in 1889, roofers complained to the Canadian Architect and Builder that the duty must come off foreign slate since the New Rockland Company could not provide the necessary supplies.