Page:Popular Science Monthly Volume 91.djvu/746

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The Robber Crab. It Prefers Coconuts, But Will Carry Away Anything

THE robber- or coconut -crab has been known for some centuries, but until lately doubts have existed as to whether or not they actually climb trees to reach the coco- nut. The photo- graph shown here, taken on Christmas Island, should dis- pel all uncertainty on the point. Al- though the giant creatures seem hor- rible as they crawl through the woods, they are easily frightened and scut- tle off backwards at the slightest alarm.

��Popular Science Monthly

��runs over sprocket-teeth affixed to the rear of a cylinder, which in turn is operated by the pressure of the finger on the trigger or hammer.

���The crab clings to the tree with the sharp points of its walking legs, scarcely using its large claws. It lives on coconuts and carrion

��The Machine-Gun Principle Applied to the Revolver

WW. McHAVEN, of Birmingham, . Alabama, feels that the revolver can be crossed with the machine-gun, with profit to the breed thus produced. He has taken the ordinary revolver principle, which involves a cylinder containing a number of chambers for cartridges and which is revolved by the action of the trigger or hammer, and for the fixed cylinder has substituted a chain of cartridge holders or chambers, to be made any length desired, so as to afford an increased number of shots without reloading. Each link of the chain carries a steel cart- ridge-holder, similar to the chamber in the cylinder of the re- volver, and presum- ably heavy enough to stand a pressure of around ten thousand pounds per square inch, which is the pressure developed by the average revolver cartridge. The chain

��5ul let carriage flange connected to form chain

��As the cylinder is revolved, the chain is brought up link by link, passing un- der rollers in the frame above the cyl- inder, the holders dropping into seats cut in the periphery of the cylinder, into which they are firm- ly held by the roll- ers. The shock of discharge is taken by the frame to the rear of the holder as it lies in position.

So here we have it, our cylinder of old-time days stretched out into the form of a chain, and that chain made any length you fan- cy. You can have a little leather reel-case strapped to the right wrist, or else a flat box, a la Maxim gun, with the chain arranged therein — and the duration of your fire is limited only by the size of the box.

Scientifically speaking, the revolver is a rough-and-ready sort of weapon anyhow, with the cartridges carried in a cylinder separate from the barrel, with the bullet leaping a gap between the two, and with the powder gases sizzing out the passage 'twixt barrel and cylinder. Hence this chain invention is not so improbable as it sounds at first. But a revolver is not a very ac- curate weapon at best, and this one with its dangling chain seems clumsy.

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