Page:Popular Science Monthly Volume 90.djvu/770

 Blow Up the Earth? Not with Dynamite

By Hudson Maxim

These wonderful facts about explosives are taken from a chapter in the author's recently published "Dynamite Stories." They indicate that to know all there is to know concerning even dynamite is to fear practically nothing. — Editor.

��WHEN one of our big army or navy cannon is fired, the time which elapses from the instant of complete ignition of the powder charge to the instant that the projectile leaves the muzzle of the gun is about the fiftieth or the sixtieth of a second, and in that time the hard and horn-like smoke- less powder ma- terial is burned through only about a sixteenth of an inch; hence the rate of com- bustion or rate of explosion of smokeless powder in a cannon is about four inches per second, while it has been ascer- tained by actual experiments that the rate of com- bustion or rate of explosion of dyna- mite and other high explosives is about four miles per second, so that the rate of con-

���If a celestial giant should touch off a bomb immedi- ately behind our earth, the earth would be thirty thousand miles away before the bomb exploded

around the sun, and

��sumption of smokeless powder, as com- pared to that of a high explosive, is as are four inches to four miles.

As the time required for the projectile to be thrown from a twelve-inch cannon is only about the sixtieth of a second, sixty of these huge guns could be placed side by side and fired by electricity one after the other, while grandfather's clock is making but one tick.

Our ideas of duration are but relative. Great as is the speed of the detonative wave, yet the speed of the earth in its orbit is four times as great. If a celestial

��giant with a huge dynamite bomb the size of the earth itself were to approach the earth in its flight through space, and de- tonate the bomb immediately be- hind the earth, it would take half an hour for the bomb to explode; that is to say, it would take half an hour or thirty minutes for the ex- plosive wave to pass through the eight thousand miles of its diam- eter. As the speed of the earth in its orbit is four times as great as that of the explosive wave, the earth would rush away, leaving the bomb about thirty thou- sand miles behind by the time it had completely ex- ploded. If the in- terstellar ether were a high ex- plosive mixture and were to be set off, by the bomb, the earth would pass on clear while coming back

��sun, about six months later, would meet the explosive wave still going. It would re- quire nearly a year for such a detonative wave to reach our sun from the earth.

Can Our Earth Be Blown Up?

We frequently hear the theory advanced that planets and suns sometimes explode from pent-up forces within them, and that our earth might possibly blow up. Now, the force exerted by a high explosive is dependent entirely upon the pressure capa- ble of being exerted by the gases liberated

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