of the velocity with which missiles must have been expelled by explosions that have taken place in the interior of the globe. We find a difficulty in believing that the nascent earth could have launched projectiles at the speed of seven miles a second. Let us then see what the sun can do.
It can be shown from observations of the solar prominences that vast masses of vapour are frequently expelled from the interior of the sun by convulsive throes with a speed of three hundred, four hundred, and sometimes nearly a thousand miles a second. Let us ponder on these facts. They are indeed most astounding, and would hardly be credible were they not supported by ample evidence of unimpeachable authenticity. The spectroscope enables the observer actually to witness the ascent of these solar prominences, notwithstanding that they are at a greater distance than ninety millions of miles. Careful measurements demonstrate the startling results which I have already stated. Of course, the present fervour and energy of the sun wholly surpasses that which could have been possessed by the earth at the phase of its history which we are considering. But remember that all we want is an explosive power in the terrestrial volcanic gases sufficient to impart a velocity of seven miles a second, nor need this be denied when we have shown that the actual velocities produced by outbreaks in the sun at this very moment are more than one hundred times as great as that modest allowance for which we ask.
Those who ponder on these facts will, I think, come to the conclusion that, though from our ordinary points of view a speed of seven miles a second seems too monstrous to be
