Index 675 



wounds, 418, 458, 479, 482-483 year Cont'd 

 Wright, Orville, 281, 284, 547, 570, leap, 151 



578 light, 165, 630 



Wright, Wilbur, 281, 284, 547, 570, yeast, 316, 369, 372, 378-379, 395- 



578 396, 444, 646, (316} 



writing, 5, 548 yellow fever, 454, 543 



X 



X-ray, 233-234, 552, 574, 646, (233) 



Zeppelin, F., Count von, 578 



Y zinc, 24, 30, 82, 208, 646 



year, zones, 119-120, 134, 646, (120) 



calendar, 151 zoology, 6, 646 



