ILLUSTRATIONS 



EARLIEST PICTURE KNOWN OF A SURGICAL OPERA- 

 TION. EGYPT, 2500 B.C 6 



ST. THOMAS AQUINAS OVERCOMING AVERROES . . 54 



DR. GILBERT SHOWING HIS ELECTRICAL EXPERIMENTS 

 TO QUEEN ELIZABETH AND HER COURT .... 72 



THE TICHONIC QUADRANT 88 



WADHAM COLLEGE, OXFORD 104 



SIR ISAAC NEWTON 112 



JOHN DALTON COLLECTING MARSH GAS .... 162 



THE FIRST SUCCESSFUL HEAVIER-THAN-AIR FLYING 

 MACHINE . 236 



