ROPE 



29 



Construction of rope. A rope is made of fibers so inter- 

 twined or twisted together as to form a thick cord capable 

 of sustaining a severe strain. The primary object of twist- 

 ing the fibers together to form a rope is that by friction 





/^"our S+rand 



& 



Three Strand 



Cab/e. 



Fig. 8 



they may be held together when a strain is applied to the 

 whole. Hard twisting has the further advantage of compact- 

 ing the fibers and preventing the penetration of moisture. 

 The steps in the manufacture of rope are as follows : 



1. The fibers are twisted into yarns in a direction called 

 "right hand," as shown at A in Figure 7. 



2. From two to eighty of these yarns are then twisted 

 together into a strand in a direction called "left hand," as 

 shown at B in Figure 7. 



3. Three of these strands for a three-strand, and four for 

 a four-strand rope are then twisted together in a direction 

 called "right hand," as shown at C in Figure 7. 



4. If these ropes are twisted together to form a cable, 

 shown in Figure 8, they are twisted in a direction called 

 "left hand." 



When a strand is twisted up, the yarns composing it are 

 untwisted; and when a rope is twisted up, the strands 



