Then, {HEAD ~ ends} of {TAIL ~ the primary struts} 311, 313, and the secondary bars 312, 314 are pivotally interconnected with the four assisting beams 321, 322, 323, and 324 by pinshaft 350 
of
Then , { HEAD ~ ends } of { TAIL ~ the primary struts } 311 , 313 , and the secondary bars 312 , 314 are pivotally interconnected with the four assisting beams 321 , 322 , 323 , and 324 by pinshaft 350
OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL 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 OTH OTH OTH OTH OTH OTH OTH OTH OTH