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increase more rapidly in some parts, and the difference would tend to 
increase ; for the generated gases would fracture the lower parts and leave 
undisturbed the more solid parts. Cavities would abound, filled with gases, 
in the disturbed portion of the crust, while the undisturbed would increase 
and tend towards any solid nucleus which may have been formed. 
The hypothesis of a previous gaseous state does not rest on reasoning 
similar to that of the fluidity, nor does it affect that reasoning. The gaseous 
theory may be true or not true. 
The second part of the Eeport treats, on the effects of subterranean forces 
on the solid crust of the earth. The fundamental hypothesis connected with 
the theories of elevation, is that large areas are resting on fluid matter 
possessing expansive force. The results of pressure are discussed, when 
applied to areas of different forms, rectangular, circular, oval ; and the 
following conclusions were obtained. 
"That two systems of fissures may result from the simultaneous elevation 
of an extensive area ; and such that the mean direction of the fissures in one 
system, at any point of that area, shall approximately coincide with the 
mean direction of the strike ; and in the other system, with that of the dip 
of the elevated beds at the proposed point.'' 
A diagram was shown to explain the law of displacement of the beds in 
connection with the fault ; the beds on the under side being raised, or on 
the upper side depressed. A second figure represented undisturbed strata 
the moment before dislocation ; the fissures having been made. The third 
figure represented the dislocations after elevation, those wedge shaped parts 
which present their broad surfaces to the elevating force being elevated 
above the others. It is supposed that the tension of the generated gases 
would be relieved by escape through the fissures, and that the uplifted 
masses would subside as represented by a fourth figure, by which a great 
horizontal pressure would be created, affecting the detached masses, which 
pressure would be greater as the subsidence increased. Three diagrams were 
intended to explain the cause of folded strata when 1st they were horizontal 
and the pressure horizontal; 2nd when the strata were sloping; and 3rd 
when both strata and pressure were sloping. 
Mr. Hopkins determines that if anticlinal and synclinal lines alternate at 
intervals not exceeding a few miles ; then the thickness of the elevated crust 
cannot be greater than th© same number of miles. He also thinks that such 
displacements are more consistent with the hypothesis of a small number of 
great movements than a very large number of small ones. However, a 
gradual accumulation of force producing slow movements might be followed 
by a sudden production of fissures and sudden elevation, and then would 
