THE PEAR. 



107 



is used thus : When one end of the wire has been made 

 fast to the wall and passed through the eyes of the 

 supporting pins as far as the half of the entire length 



Fig. 95. Fastener. Fig. 96. Tightener. Fig. 97. Key. 



of the line, it is brought through one end of the tight- 

 ener, through the centre of the axle, and out at the 

 opposite end, then through the eyes of a number of 

 pins sufficient for the second bolt of the wire, then 

 fasten the wire at the other extremity, and tighten a 

 little. Drive the pins into the wall at their proper 

 distances, then tighten the wires as much as possible, 

 using the key (fig. 97). When sufficiently tight, 



