Bruner Sidewalk Lights - 1911 Catalog - Page 15

SPECIFICATION -- Continued
        The glass shall not be indented; the reflecting part of prisms shall be entirely below bottom of slab. The ribs shall not be less than 3½ inches deep, and shall run in the direction in which the light is to be thrown. The main reinforcement shall be held in suspended wire yokes, one to each glass; the reinforcement in slab shall be round rods, placed between each row of glass in both directions. The concrete shall consist of one part of first-class Portland cement and two parts of sharp and clean sand. The paving shall be divided into suitable sections, and then shall have patent expansion joints to enable the panels to expand and contract without leakage or strain.
PRICE
        Considering the effectiveness of illumination by this system it is easily the cheapest, not by the square foot, but by the units of light furnished beyond the immediate area beneath this paving. In some cases it furnishes at the same time more light also immediately underneath. Too often no thought is given to this point, and the owner is allowed to think only of the cheapest bid for covering an opening in his sidewalk or over an area, without considering the amount of illumination he may get from the work offered.
        See two cuts of adjoining panels on pages 18 and 19, as seen from basement. One of them marked (B) being our system, and the other marked (A) being another system used at this same building. The top surfaces of the two panels are alike in appearance, but below only the "Bruner" panel can throw light into the rear of the basement, while in the other panel marked (A) no light at all can be seen from the back part of basement at an equal distance from the sidewalk.