Penny Blood: Serial Sensation and Working-Class Entertainment — page 18: what you’re looking at

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

CHAPTER I. ON UNDERGROUND TEMPERATURE. The rise of temperature on descending into the earth—The causes which have been assigned for it—Attempts te determine the law of increase by ob- servation—Their results—Deep bore-hole at Sperenberg and methods of observation used there—General effects of convection currents in a bore-hole —Tabulated observations at Sperenberg—Anomalous result supposed to be deducible therefrom—Anomaly explained—General law of average rise of temperature not impaired thereby—Hot springs and volcanos prove that the rise of temperature continues, but do not inform us whether the law near the surface obtains unaltered for all depths. THERE is no fact more firmly established in terrestrial physics than that the temperature of the rocks of the earth’s surface increases with increasing depth. Observations wpon this subject have been made in all parts of the world, and the same result has been everywhere arrived at. Even in the frozen soil of Yakoutzk, in Siberia, this increase of temperature is found to prevail, although the ground is con- gealed to the whole depth penetrated’. In all mining opera- tions this gradual increase of temperature becomes a very serious consideration, rendering human labour at great depths a very severe trial to the constitution of the workman. And 1 The increase of temperature at Yakoutzk, although the soil is frozen even beyond the depth reached, proves that this freezing is owing to the present “4 low mean temperature of the locality, and that it is not a residual effect of a former glacial and still colder period; for if that were so the strata would be © now warmer above than below, whereas the reverse is in fact the case. The average temperature for the year is —8°6, R. or 12°7, F. Prof, Milne, in ‘*‘ Geol. Mag.’”’ N. 8. Vol. iv. p. 518. F 1 GONG oOo n(C©)