{HEAD ~ A second form} of the apparatus provides for a pair of {TAIL ~ conductors} not in mutual contact but each in contact with the test contact member when the latter is in the rest position 
{ HEAD ~ A second form } of the apparatus provides for a pair of { TAIL ~ conductors } not in mutual contact but each in contact with the test contact member when the latter is in the rest position
HEAD HEAD HEAD HEAD HEAD HEAD HEAD 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 OTH OTH OTH OTH