Penny Blood: Serial Sensation and Working-Class Entertainment — page 254: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

cH. xvil.] PHEORY OF VOLCANIC ENERGY. 237 ‘We took p at the value ? of the weight for friction. We will take it as equal to the weight for the adhesion, since that is probably greater than the friction, although its ratio to the friction probably diminishes as the pressure increases. Hence w= $y, .*. the work = § “elt But the whole work on a vertical section was found to be - ek*; hence the whole work along the plane of shearing is 24 of the work along the vertical section. This work will not be evenly distributed, but will be greatest upon the unit of the length nearest A, where the space moved over will be eA B, and the force upon it is yw’. Hence work upon the last unit = »'eAB, , P,-P =e ———*; upon the suppositions made, this becomes = 4 Pek, And the work upon a square mile of section on the same suppo- sitions was found to be 4 P5ek. Hence the work, and therefore the heat, upon the last unit of the plane of shearing, where it will be greatest, 1s only one- fifth of the work and heat respectively on a unit of the vertical section. This result seems unfavourable to the view that the heat arising from friction of the rocks along horizontal planes can account for the heat concerned in producing even metamorphism. It must be fully understood that the results just arrived at with respect to the heat developed at a vertical section, as well as along the plane of shearing, have reference not to any pro- bable values, which under the assumed conditions could anise, but to a superror limit which must be greater than the greatest possible. In fact they involve several impossible assumptions, all of which make it too large. These are:— GONG oOo SS (CO)