ON PADDLE WHEELS. 139 



Whence, 



Log. 3 z 2 sin. f 

 2 p 2 sin. f 

 p 2 cos. f 2 sin. 



Sum of positive terms =333-769 



Zap sin. f = 1-9844123 3 ap sin. f = 96'474 

 3pzt =2-3325255 3 p z =215-043 



Sum of negative terms =311-517 



S'" = 22-252 



Log. S"' = 1-3473691 



Tr 2 = 0-9942998 



n 3 = 3-5282738 



b = 0-9420081 



/ = 0-3979400 



w = 1-8070274 



m = 1-2041200 



p = 0-8813691 



-^ =-2-1912490 

 1 



" 22275000 



Log. H.P.E. = 1-9458386 



H.P.E. = 88-275. 



When a steamer is heavily laden, the wheels, from their excessive immersion, act less 

 advantageously, besides reducing the number of strokes of the engines by the great number 

 of floats immersed at once, and their great obliquity, which increases the resistance. Under 

 these circumstances the speed of the vessel-is naturally diminished, and it may in some cases 

 be desirable to bring out the full power of the engines, as it is called ; that is, to enable them 

 to make the full number of strokes they were calculated for, in order to prevent so great a 

 loss of speed. We know but one mode of effecting this, and that is by reefing the floats, or 

 shifting them from the circumference nearer to the shaft. This method is attended at present 

 with too much difficulty and danger to allow of its being put into general practice ; but we 



