M,l M I I 



npp. -e you takfi a boiler the <ame leng.h and 

 'ie same material, but <So inche> in diameter. The 



' >,OOO -f 2 ) = 560 



and the safe working pressure would be $(>o ~- 6 = 



93 Ibs. 



You will see by ibis that the diameter has much lo do 

 with Ihe safe working- pressure. 



All of which is nice for you to know, and it may 



on a higher course, but it will nut make you handle 

 your engine any better on the road or in the held. 



Suppose we give yon a little touch of rules, and for- 

 mulas in boiler making. 



For instance you want to know the per cent of ^trengih 



ingle riveted and double riveted as compared to 

 in-n. Some very simple rules, or formula ; ppii- 



cable. 



Find the per cent of strength to the solid iron in a 

 single-riveted seam, J4 inch plate. \s inch rivet, pitched 

 or spaced 2 inch center duce all to decimal 



:i. as it simplifies the calculation; ]/ 4 - 

 inrh rivets will require eleven-sixteenth inch hole. \\\\- 

 bole is supposed to be filled by the rivet, after driving. 

 consequently this diameter is used in the calculation. 

 Heven-sixteenths inches equals .O' 



First find the per cent of strength of the sheet. 



