whereby {TAIL ~ the expansion} of said pressure transmitting medium by said driving means is concentrated at {HEAD ~ said elastic wall portion}, to move said elastic wall portion to drive said printing element 
whereby { TAIL ~ the expansion } of said pressure transmitting medium by said driving means is concentrated at { HEAD ~ said elastic wall portion } , to move said elastic wall portion to drive said printing element
OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH