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CHAPTER IX.

CONDITIONS AS TO FORM AND STRUCTURE IN BUILDINGS, WHICH MODIFY THE EFFECTS OF SHOCK—FIVE PRINCIPAL CONDITIONS.




It will now be necessary to refer to the special effects produced, by the architectural figure, and other particular conditions of buildings, &c., upon the principal phenomena due to the shock upon them, as just described. The treating of this might give rise to almost endless details; reference will therefore only be made to a few of the salient conditions, and their modifying effects, from which the intelligence of the observer can deduce, all others that may come before him.

What has preceded has been exemplified, by an imaginary roofless rectangular building, on level ground, and without any apertures. We have now to discuss how the actual conditions of buildings as we find them (having those of Italy in view primarily, however) affect and modify the results. We may discuss this under the following heads of effects, produced by the wave of each class, as modified by the following conditions, viz.:—

1st. The form, magnitude, height, and unsymmetrical character of construction.
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