240 NATURE'S TEACHINGS, 



scope, when it assumes the most curious resemblance to the 

 kris. Its mirror-like surface looks as if it had been very roughly 

 treated with a coarse file, while its thin and delicate edge, 

 which is perfectly smooth to the eye, and which will pass 

 through a piece of stretched wash-leather without any apparent 

 opposition, becomes as rough and jagged as that of the Malayan 

 weapon. 



Take even, for example, the common butcher's knife, which 

 is perpetually being sharpened on the " steel " that hangs at 

 his belt. The reader may observe that the butcher does not 

 rub the blade of his knife backwards and forwards on the steel, 

 as unskilful persons do. Rapid as is the movement gained by 

 constant practice, any one may see that the blade is always 

 moved in one direction, so as to force the microscopical teeth to 

 point one way, and so to act as a saw when the knife is drawn 

 across the meat. 



The power of these teeth or notches may be inferred from 

 a well-known fact. If a razor, no matter how sharp, be pressed 

 upon the human skin without any " draw," it will indent the 

 skin, but not cut it, while the slightest drawing movement will 

 cause a deep wound. It is the knowledge of this fact that 

 enables an expert swordsman to sever an apple placed on the 

 palm of the bare hand, without even scratching the skin. I 

 have witnessed this feat, and at once saw that it was due to the 

 absence of any " draw " to the cut. The apple was laid on the 

 palm of the hand, which was opened as widely as possible, so 

 as to flatten it. The sword was then brought down on the apple 

 with a sort of chopping movement, so that, although it indented 

 the skin, it did not even inflict a scratch. 



By the use of the " drawing " movement, the same sword 

 severed a gauze veil laid across it, the two halves floating in 

 opposite directions. By the same cut, I have seen some asto- 

 nishing feats performed with an Indian sword now in my collec- 

 tion, the objects of attack falling asunder as if by magic, withoul 

 any apparent force being used. 



HAVING now glanced at the principle of the Saw, we will 

 proceed to some of its details. 



The simplest form of Saw in existence is that which is in use 

 among the Australian natives, and consists of obsidian flakes 



