the carriage of each push button having its own tongue element projecting rearwardly therefrom in {HEAD ~ the predetermined direction} of {TAIL ~ depressing movement} thereof, 
of
the carriage of each push button having its own tongue element projecting rearwardly therefrom in { HEAD ~ the predetermined direction } of { TAIL ~ depressing movement } thereof ,
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH