Rod-making. 



length of the diagram, that 9 inches does 

 to the working length of the rod 116 

 inches (so very nearly that we may neg- 

 lect the error). Draw straight lines at 

 a right angle to the axis of the rod at 

 each of these 13 divisions, and number 

 them as in the diagram, calling each 

 space so formed 9 inches long. It will 

 be seen that we have thus determined 

 the diameter of the rod for every 9 

 inches of its working length; and that 

 to find what it should be at any point 

 say 54 inches from the handle, for ex- 

 ample all we have to do is to measure 

 the perpendicular line at the point 54, 

 and we have it. 



From the diagram already constructed 

 you have determined where the ferrules 

 shall be located, and also the inner di- 

 ameter of the outside or female ferrule. 

 Now having cut your wood about an 

 inch longer than the ultimate length of 

 the proposed joint, square it with the 

 plane. Then 

 drill two holes, 

 a and b (Fig. 

 35), through 

 each of the 

 joints at right 

 angle with one 

 another: one, say at half an inch, and 

 the other at three-quarters from that 

 which is to be the larger end. 



Inches. 

 0.. 



9. 



18 



27. 



45. 



54. 



83. 



7-2. 



81.. 



90. 



99. 



108. 



163 



if in. 



116. 



in. 



Fisj. 34. 



