1224 
DECIMAL CLASSIFICATION 
X rays diagnosis pathol. 616.077 
electricity 537.53 
mesology 612.0144817 
radioactivity’ 539.7 
Xalanga history 968.653 
Xanorphica 787.4 
Xanthian marbles 732 
Xenacanthini paleontol. 567.31 
Xenarchi 597.58 
Xenocrates anc. philos. 184.3 
Xenon inorganic chem. 546.295 
Xenopeltidae 598.121 
Xenophanes Gk philos. 182.3 
Topics in black face type are subdivided. Superior figures refer to the tables at the end of this index