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THE MECHANISM OE BICYCLES. 
There is a resistance due to vibration which may be neglected if all 
the parts such'as mud guards, brake, etc., are firmly attached and 
the machine is of such a weight that the frame is suitable for the 
weight of the rider and the nature of road usually met with. 
There appears to be a desire on the part of many riders to obtain a 
very light machine, but if the machine is required for all round riding 
it should be remembered that after a certain point is reached, this 
saving of weight is only obtained at the expense of strength, rigidity 
and durability. What will do for a racing track will not be suitable 
for climbing a hill or riding on the Woolwich roads. The only 
remaining resistance is that due to the gradient and the formula. 
R, 
W- 
(where h = rise, l = length of road) 
is the same for bicycles as for all other bodies. When goingdown hill, 
R 5 of course acts with the rider instead of against him. 
I have reproduced a diagram (published by Mr. Landis in the 
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