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Page:Popular Science Monthly Volume 70.djvu/401

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beautiful mountain road from Kingston to Newcastle was in the line of greatest intensity. But though spurs showed considerable destruction and in places the road slipped off the face of the steep slopes (Fig. 11), or portions of the hills slipped down on the road carrying it away or obliterating it by landslides in many places, yet the destruction was caused more by the unstable position of the road, or of these masses of earth, rather than by the intensity of the shock. At Newcastle, moreover, the buildings for the most part were not damaged to any great extent, except as their location on a terraced slope or on the crest of a short divide would place them in a position of unstable equilibrium. Similar destruction might be caused by a severe rainstorm,

PSM V70 D401 Destroyed carriage road to newcastle in the blue mountains.png

Fig. 11. Destruction of the Beautiful Carriage Road to Newcastle, built on the steep slopes of the Blue Mountains.

or, in the northern countries, by frost action as well as by earthquake waves.

From the investigation of the many cracked walls at Kingston, the amplitude of the wave motion (as one might expect on alluvial foundations) was considerable. Spaces from half an inch to two inches were left in massive walls. Floors and ceilings were pulled from the shallow supports in many cases and caused destruction in more instances than would have been necessary had there been greater foresight used in the manner of building. From an open circular well of masonry some twenty feet in diameter water was thrown up some eight feet and over the northeastern lip of this well. A brick pier in a fence was thrown to the eastward beyond its arc, some two thirds the length of its radius. At the same place large slabs of marble were moved along