{HEAD ~ The pipettes}, 40 and 42, are positioned and operated by {TAIL ~ a pipette mechanism} 44 mechanically connected to the pipettes 40 and 42, as indicated by dashed lines 
{ HEAD ~ The pipettes } , 40 and 42 , are positioned and operated by { TAIL ~ a pipette mechanism } 44 mechanically connected to the pipettes 40 and 42 , as indicated by dashed lines
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH