{TAIL ~ Certain masses} oscillating about {HEAD ~ the z axis} are tiltable about the x axis, while some others are tiltable about the y axis 
{ TAIL ~ Certain masses } oscillating about { HEAD ~ the z axis } are tiltable about the x axis , while some others are tiltable about the y axis
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH