Lightning rods are especially required on ice houses. Being often the most prominent object in their locality, the electric fluid finds its readiest path through them, and the escaping vapor and much of the material used in their construction add to their exposure. Copper strips, terminating in forked points, raised above the cone of the roof, fifty or seventy-five feet apart each way, provide ample protection. A line of points across the house should be connected, and the copper strips extended, without any break or interruption, into the ground. They should be buried several feet below the surface, and if they terminate in a drain or other damp place, their efficiency is increased.
FIG. 51. ELEVATION OF PLATFORM ALONG TRACKS FOR LOADING CARS.
FIG. 52. PLATE D. SECTION OF LOADING PLATFORMS.
The floor of each room is graded slightly toward the center, and a trench dug through the center from end to end. It should have a grade toward the front of the house of about two inches in a rod. At the rear of the house it may be nine inches square, gradually increasing to double this size at the front of the house. Lateral drains, alternating on either side, are desirable. If the surface drainage sets toward the house, it should be intercepted and conducted away. After the trenches are made they are filled with broken stone or cobbles about nine inches deep at the start, and double the depth at the front of the house. The side trenches may be six or eight inches wide, and filled about the same depth.
On top of the stones, shavings, straw, reeds, or other porous filling, is placed, to the level of the floor. The entire floor is now covered with a layer of charcoal, or with coal ashes placed several inches deep. On top are laid boards, not too closely placed, with length toward the main drain. The spaces between the boards form channels to conduct the waste water to the drains. Where the drains emerge from the house they are trapped, to prevent any air currents from entering through them, and collected into one or more main channels.
[Plate A] illustrates the drainage plan, and a section view is presented in [Plate B]. In porous soils, which can be depended on to carry off the wastage, drains are not so necessary. For very large houses, however, they should not be entirely neglected. In warm climates and for city supply houses, cement floors are the best.
For loading cars for winter shipments, the platforms illustrated in plates A, C and D are used for handling large quantities. The ice cakes are elevated on the incline to runways (see R, in Plates [A], [C] and [D]), and slide by gravity until landing on the platform. An endless chain with cross-bars passes over the top of this platform, carrying a cake before each bar. Where a railroad siding is placed on both sides of the platform the work is expedited, as no delay is occasioned by waiting for cars, a loaded train being pulled out and empty cars run in on one track, while loading continues on the other.
