Fig. 9.—End-framing of Large Building.
For a narrow house, if the roof be a gable, a central upright at each end of the building gives support to the ridge-pole from which the rafters run to the eaves ([fig. 8]). If the building be wide, a transverse beam traverses the end of the building on a level with the eaves, supported at intervals by uprights from the ground; and upon this short uprights rest, supporting [pg 19] another transverse beam above, and often three or more tiers are carried nearly to the ridge. Upon these supports rest the horizontal beams which run parallel with the ridge-pole, and which are intended to give support to the rafters ([fig. 9]).
In the case of a wide gable-roof there are many ways to support the frame, one of which is illustrated in the following outline ([fig. 10]). Here a stout stick of timber runs from one end of the house to the other on a vertical line with the ridge-pole, and on a level with the eaves. This stick is always crowning, in order to give additional strength. A few thick uprights start from this to support the ridge-pole above; from these uprights beams run to the eaves; these are mortised into the uprights, but at different levels on either side in order not to weaken the uprights by the mortises. From these beams run short supports to the horizontal rafters above.
Fig 10.—Roof-frame of Large Building.
The roof, if it be of tile or thatch, represents a massive weight,—the tiles being thick and quite heavy, and always bedded in a thick layer of mud. The thatch, though not so heavy, often becomes so after a long rain. The roof-framing consequently has oftentimes to support a great weight; and though in its structure looking weak, or at least primitive in design, yet experience must have taught the Japanese carpenter that their methods were not only the simplest and most economical, but that they answered all requirements. One is amazed [pg 20] to see how many firemen can gather upon such a roof without its yielding. I have seen massive house-roofs over two hundred years old, and other frame structures of a larger size and of far greater age, which presented no visible signs of weakness. Indeed, it is a very unusual sight to see a broken-backed roof in Japan.
The beams that support the roofs of the fire-proof buildings, or kura, are usually rough-hewn and of ponderous dimensions. It would seem that here, at least, the foreign method of trussing might be an economy of material, besides giving much greater strength; and yet the expense of reducing these beams to proper dimensions, in the absence of saw-mills and other labor-saving machinery, with the added expense of iron rods, bolts, etc., would more than counterbalance the saving of material ([fig. 11]). In [Fig. 11] is shown the universal method of roof support; namely, horizontal beams resting upon perpendicular walls, these in turn supporting vertical beams, which again give support to horizontal beams. That the Japanese have been familiar with the arch is seen in some of their old stone bridges; but they seem as [pg 21] averse to using this principle in their house-architecture as were the Egyptians and Hindus. Fergusson, in his illustrated Handbook of Architecture, page xxxv, says: “So convinced were the Egyptians and Greeks of this principle, that they never used any other construction-expedient than a perpendicular wall or prop, supporting a horizontal beam; and half the satisfactory effect of their buildings arises from their adhering to this simple though expensive mode of construction. They were perfectly acquainted with the use of the arch and its properties, but they knew that its employment would introduce complexity and confusion into their designs, and therefore they wisely rejected it. Even to the present day the Hindus refuse to use the arch, though it has long been employed in their country by the Mahometans. As they quaintly express it, ‘an arch never sleeps;’ and it is true that by its thrusting and pressure it is always tending to tear a building to pieces. In spite of all counterpoises, whenever the smallest damage is done it hastens the ruin of a building which, if more simply constructed, might last for ages.”
