ELASTICITY OF RODS. 37 



should droop very little from the straight line. 

 To render this somewhat less indefinite, I subjoin 

 two figures. 



Fig. 2. Fig. 1. 



1, 



Scale 1-1 Oth of an inch to the foot. 



A to B (salmon rod) 18 E to F (trout rod) ..14 3 



BtoC .......... 1 5 FtoG .......... 1 6 



B to D .......... 5 10 F to H .......... 5 4 



In Figure 1, AB is supposed to be my eighteen 

 foot four-jointed salmon-rod, straight; when held 

 at the but horizontally, as Mr. Ronalds says, it 

 will, of its own weight assume the line AC, the 

 point c diverging seventeen inches from the 

 straight line, or the height at which A is held. 

 And I find on attaching to the point B a half 

 pound weight, it will bring it down, as A D, to D, 

 which is five feet ten inches and a half out of the 

 straight line. 



In Figure 2, EF is my fourteen feet three 

 inches and a half three-jointed trout- rod, straight. 

 It droops eighteen inches, as to G, of its own 

 weight ; and to H, equal to five feet four inches, 

 by a quarter of a pound weight attached at the 

 point, having, therefore, little more than half the 

 elastic strength of the salmon-rod. These two 

 facts may be perhaps some guide as to a 



