730 



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. 



