The other end of the arch block is supported on a spring in {TAIL ~ a blind hole} in {HEAD ~ the arched notch} 
The other end of the arch block is supported on a spring in { TAIL ~ a blind hole } in { HEAD ~ the arched notch }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD