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TOOLS FOR DRILLING. 





pulley, about 3 cm in diameter, and 3 or 4 cm long, fixed upon an iro 

 axis, l cm thick and from 20 to 24 cm long. . The axis may be made ( 

 a suitable piece of bar iron, and the wooden pulley fixed upon it b 

 a turner. A square bar of iron of the proper length can be bougl 

 at any ironmonger's ; by filing, it may be made eight-sided, whic 



looks better, or it may simply be left as it is. The face at each en< 

 is filed plane, and in the centre of each face a small mark is mad> 

 with the centre-punch. With the first blow of the hammer th< 

 punch is struck rather gently. If the slight mark thereby producec 



