SHEARS AND SCISSORS. 229 



A well- known example of a single cutting blade is found in 

 the guillotine. In the earliest times of this invention an 

 ordinary axe-head was suspended above the neck of the criminal. 

 It was found, however, that its operation was very uncertain, 

 simply because the blow was a direct one, and not oblique. The 

 blade was then set obliquely, as in the present machine, and 

 its effect was absolutely certain. 



Perhaps some of my readers may be swordsmen, and there- 

 fore knowthe power of the "drawing cut," by which a great effect 

 may be produced with very little apparent exertion. Even in 

 the simple operation of cutting bread we always use the knife 

 diagonally, though perhaps we may be ignorant of the principle 

 of the inclined plane. 



Next comes the principle of the lever, as exemplified by the 

 handles of the scissors. By lengthening these handles, the 

 power of the blades is enormously increased, as may be seen in 

 the various shears in any great iron-works, which cut through 

 thick iron as if it were butter. Our own garden shears for 

 trimming borders show very well the power of the long arms 

 and short blade. 



IN the animal world we find many examples of natural shears, 

 one of the best of which is afforded by the jaws of the Tortoise 

 or Turtle. Owing to the manner in which they feed, whether 

 they be vegetarians or carnivorous, their jaws are made for 

 cutting, and not for lacerating or mastication. They have IK 

 teeth, but each jaw is furnished with a horny edge, as sharp a&> 

 a knife-blade, and very strongly made. With these jaws the 

 animal can shred to pieces the objects which it attacks, just as 

 if it had been furnished with a pair of veritable shears. Any 

 one who has possessed an ordinary Tortoise must have noticed 

 the havoc which it will occasionally make in a garden. I had 

 one of these reptiles for some years, and was obliged to keep it 

 under restraint, in consequence of the power of its jaws. 



Being a Tortoise of discrimination, it took a great fancy to 

 the strawberry beds, and invariably picked out the ripest and 

 best-flavoured fruit. Reversing the usual proverb of making 

 two bites at a cherry, the TortoisQ always took two bites at a 

 strawberry, and sometimes three or /bur, according to its size. 



At last, I was obliged to restrain it by boring a hole in the 



