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 roof and the light framework in Japanese erections are ill-suited to withstand these shocks, and I believe my opinion to be sustained by the truest principles of mechanics. This, however, is hardly the place to enter into a disquisition upon that subject. I am also of opinion that a solid erection, properly constructed, will afford the greatest safety daring an earthquake and at the same time is the only one which will give reasonable security against fire, wind or the other natural disturbances. An appliance has been devised by a well known English engineer for the purpose of counteracting the disturbing force of an earthquake, the principle of which is very simple. It was said by him that the movement given to the foundations of a building is transmitted with accelerating force to its summit, and that to destroy this the simplest method was to make a break in the continuity of the structure. The designer, therefore, proposed that buildings should be made in two parts, the lower part to be firmly embedded in the earth, the upper to rest on balls which are made to roll in inverted cups. A sudden movement in the lower part would not, then, be transmitted to the upper on account of this break or joint in the structure, and the experiments made shew that in point of fact this theory was perfectly correct. He procured this idea from seeing in Japanese drawings the uprights of their houses resting on round stones, imagining this to be done in order to give them as slight a hold of the earth as possible. But from enquiries I have made this does not seem to have entered the minds of the Japanese, and the only way they can account for the uprights being placed on round stones is to keep the wood away from the moisture of the ground and because round boulders are move easily and cheaply procured than square stones. The impracticability of this scheme, which, however, deserves a fuller trial than it his yet had, arises, in my mind, from the fact that a house resting on balls is liable to be swung and rocked about in gales of wind to such an extent as to render it unfit to live in. I may mention that the tables on which the apparatus of some of the