THE YOUNG FARMER'S MANUAL. 371 



tenacity and hardness they would lack a very important quality 

 -fineness of particle. 



530. Now good steel possesses every desirable quality for mak 

 ing the best of edge tools. It possesses refinement of particles, 

 and is capable of being made very hard and brittle, as glass, or 

 tough and soft, as wrought iron ; or any degree of hardness and 

 tenacity combined, from its softest to its hardest condition, may 

 easily be secured. Many kinds of tools are made wholly of steel; 

 and some are made of a part iron, and faced with steel ; and some 

 are made of entire steel, excepting the shank or the eye. 



531. Framing chisels, for example, are made with the whole 

 face steel and the back iron ; but firming chisels are usually all 

 steel. Large, heavy tools, the edges of which are bevelled only on 

 one side, are made with a steel face, for the sake of economy in 

 the cost of tools, and are just as good, and sometimes better, than 

 if they were all steel. The cutting edge of an axe, or a pick, or 

 crowbar, or any other tool the edge of which is bevelled on both 

 sides, must be all steel for a few inches back of the cutting edge. 

 Large knives for some kinds of straw-cutters, shingle-machines, 

 and such like, the edges of which are bevelled only on one side, 

 are just as good, and much cheaper, by having their faces laid 

 with a thin plate of steel. When it is desirable to have tools of 

 a given size, they should always be forged a very little larger, 

 wider, and thicker than it is necessary to have them, so that there 

 will be room or space for finishing them up well. The forging 

 should be done as true and smooth as practicable, and the tools 

 partly ground or filed off a little, and then tempered. 



TEMPERING EDGE-TOOLS. 



" The tempered metals clash, and yield a silver sound." DRTDEW. 



532. Tempering edge tools is the art of giving them a certain 

 degree of hardness. If a tool be made of the very lest of steel, 

 and has not the correct temper, it is in one respect no better than 

 if it were made of steel of a very inferior quality. It requires the 

 exercise of much skill and wisdom to temper tools right. A man 



