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admirably, the making of bricks, so as to turn out both a cheap and reliable article, is a process requiring such entirely different methods of work that their knowledge in the former is not of much avail to them. The selection of the clay, its puddling and the shaping of the bricks are at present all done more or less carelessly and without method, but it is in the burning of the bricks that their principal defect lies. Their kilns are formed in the shape of a cone and are, when charged, generally filled to the top with bricks. A wooden fire is inserted at the bottom and the heated air is allowed to find its way through the large mass of bricks to the top of the kiln.—Those bricks at the bottom, we naturally find, are overburnt and cracked while those on top are quite insufficiently burned. A very small proportion only of really reliable bricks is therefore got from each kiln. I am informed that very excellent bricks are procured in Kobe and Osaka, which are made at Sakai, but I have not had an opportunity of testing these. I have, however, put bricks from various other parts of the country to the ordinary tests and the results are anything but satisfactory.
The ordinary bricks in use in London absorb after immersion in water not more than 1/15th of their own weight and they withstand a pressure of 800 lbs. on the square inch. The ordinary bricks made in Yedo absorb 1/5 of their own weight of water, and will not stand more than 300 lbs. per square inch; that is to say, they are three times as porous as they ought to be and less than half of the strength they should be. Bricks made in various other parts of the country shew almost the same results. The best which I have had opportunity of trying were those made at Hakodate; they stood fully the standard crushing strain but absorbed far too much water. Such bricks are in my opinion quite unfit for building purposes. Their actual strength, when new, may be sufficient for the small erections built in Yokohama, but their porosity renders them liable to rapid disintegration, and to actual rapid destruction from severe frost, while houses built of them must, under any circumstances, suffer from continually
