LIST OF PLATES xi 



PLATE VII 



1. Bacillus anthracis. Cover-glass Preparation of Blood of Guinea-pig. 



X 750 



2. Spirochcete pallida. X 1500 



3. Streptococcus pyogenes. X 1250 



4. Bacillus typhosus. Cover-glass Preparation showing Flagella. X 1250 



5. Micrococcus gonorrhoea. Cover-glass Preparation of Pus. X 1500 



6. Bacillus of Leprosy in Skin. X 1250 



PLATE VIII 



1. Diatom, Navicula lyra. X 850 



2. Podura Scale. (Lepidocyrtus curvicollis). X 1750 



3. Podura scale. (Lepidocyrtus curvicollis). X 2500 



4. Diatom, Pleurosigma angulatum. X 1000 



PLATE IX 



1. Diatom, AmpTiipleura pdlucida. X 1500 

 25. Diatoms, Navicula rhomboides. X 750 

 6. Diatom, Amphipleura pellucida. X 1500 



PLATE X 



1. Metal Surface, of Tin and Antimony. X 20 



2. Metal Surface, of Silver and Copper. X 250 



3. Cemented Steel, showing Carbide of Iron. X 100 



4. Metal surface, Manganese Sulphide in Steel. X 1000 



LIST OF ILLUSTRATIONS 



FIQ. PAGE 



1. Wales type of Microscope (Swift) . . . . . .10 



2. Zeiss Microscope with Photo -micrographic Stage . . .12 



3. Van Heurck Microscope (Watson) . . . . .13 



4. Leitz Stand, la with English Foot . . . .15 



5. D.P.H. Microscope (Baker) 16 



6. Effect of Oil Immersion compared with Dry Lens ... 20 



7. Increased Penetration due to stopping-down of Objective . 23 



8. Photographs of Abbe Test-plate 3] 



9. Apochromatic Objective with Correction-collar (Zeiss) . . 33 



10. Sliding Objective-changer (Zeiss) ...... 37 



11. Compensating Eye-pieces (Zeiss) ...... 39 



12. Projection Eye-pieces . . . . . .44 



13. Correction for Spherical Aberration . . . . - . . 48 



14. Zeiss Centreing-collar used as Condenser . . . . 50 



15. Path of Rays in Paraboloid Condenser ..... 57 



16. Frosted Silver-leaf Film on Glass . . ... .62 



17. Reflecting Illuminator for Low Powers . . . . . 66 



18. Vertical Illuminator for Opaque Objects (Watson) . .66 



19. (Leitz) ... 69 



20. Path of Rays in Watson's Subsidiary Achromatic Lens . . 71 



21. Collecting-lens Systems . - . v * . . . 72 



22. Oil Lamp (Baker) . . . ...... .76 



23. Lime-light Jets . . . . .'.".". 83 



24. Lime-light Jet on Saddle-stand . . . . . ' .86 



25. Adjustable Lime-light Tray (Gwyer Jet Co.) . , , . 87 



26. Nernst Electric ' Luna ' Burner 89 



