Vlll 



PLATES. 



r PAGE 



The Motion of a Perfect Fluid 56 



Photomicrographs of Sections, showing Struoture of the 

 Brain 126, 128, 130, 132 



Apparatus used in the Liquefaction of Hydrogen 216,471,476,478,737 



The Viper 244 



Turbine Engines of the Viper .. .. .. .. .. 244 



Microscopic Preparations, illustrating Professor Clowes' paper 

 on Bacteria and Sewage — Figs. 1-8 .. .. .. 320, 321 



Illustrations to Sir Andrew Noble's paper on Some Modern 

 Explosives — Hates I, II ; figs. 1-10 



330, 332, 334, 336, 338, 340, 342 



Simplon Tunnel— Plates I-V 432, 434 



