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WISCONSIN STATE AGRICULTURAL SOCIETY. 
lation. It will not be very strange if at some future period, it 
should be demonstrated to the world that this form of mechan¬ 
ical force has played an important part in earthquake pheno¬ 
mena, and in lifting islands, and even continents from the 
ocean’s bed. From the highest point of tension to which water 
in the form of vapor can be wrought by heat, down to mere 
thermal waters that bubble up through fissures in the rock, the 
mechanical and chemical powers of water under the influence of 
heat are beyond anything we know of, or even can conceive of, 
in connection with the formation and transformation of mat¬ 
ter and force as presented in the crust of the earth. 
Stratified rocks, then, forming over these fractures and dis¬ 
locations will be acted upon only by this form of mechanical 
force, and the fissures produced in these rocks over these liues 
of mechanical disturbance will assume forms conforming to 
the action and reaction of this force with the force of cohesion 
that will oppose it in the heterogeneous mass of rock above. 
To generate this form of force, and to keep it active through 
vast periods of time, it is not always necessary that we should 
have a mass of cooling granite or trap as a source of heat. 
Stratified rocks, formed over similar fractures in older forma¬ 
tions, such as the azoic, would be subject to similar conditions, 
and present similar phenomena. 
I have already stated that fissures produced by the action of 
these forces, are sufficiently distinct to be divided into two 
classes cf fissures; and have called one form of force plutonic, 
the other hydro-plutonic. These terms may not be such as a 
scientific man would use, but they will answer my purpose 
very well. I use them only as a mark of distinction between 
these forces and their results, or rather between these forms of 
forces and their results, for they are only modified forms of the 
same force; one being heat acting in, and through, igneous 
matter as a medium; the other, heat acting in and through 
water, as a medium. 
Taking this as a basis of classification we shall have as a 
natural consequence, fissures that are produced by each of 
these forms of action; and also mineral veins and ore deposits 
