VARIOUS FORMS OF BUILDING.
145
gravity above the base of fracture, as in the preceding
![](//upload.wikimedia.org/wikipedia/commons/5/52/1857_Earthquake_fig._104.png)
equations,
or
of Fig. 104, and Equations XII., XIII., &c., &c., in which
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and
, as before, the distance of the centre of gravity from the axes of inceptive rotation, we have
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(XXIX.)
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The sign
applying to the first semiphase, and that
to the second semiphase of the wave.
7th. In the case of a solid cube, fractured from its horizontal base, by subnormal wave.
Substituting for
its value, and also for
,
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we obtain
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(XXX.)
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