{HEAD ~ The arch block} 12 is a biased or forced by the spring 13 into {TAIL ~ engagement} with the ratchet wheel 11 to limit rotary motion of the ratchet wheel 11 to one direction 
{ HEAD ~ The arch block } 12 is a biased or forced by the spring 13 into { TAIL ~ engagement } with the ratchet wheel 11 to limit rotary motion of the ratchet wheel 11 to one direction
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH