CONTENTS. XXV 



MICROSCOPY. 

 a. Instruments, Accessories, &c. 



PAGE 



Bausch and Lomh Optical Compam/s " Professional " and 



'■'■Investigator" Microscopes. (Figs. 'k-Q) Parti 110 



Crouch's Histological Microscope. (Fig. 7) „ 114 



Sidle' s New " Acme" Microscope „ 115 



Tolles-Blackham Microscope. (Figs. 8-10) „ 115 



Beflection from the inside of Body-tubes „ 118 



Adaptation of the " Society" Screw to Draw-tubes .. .. „ 118 

 Br. Royston-Pigotfs General and Transfer Finder. 



(Fig. 11) „ 119 



Angular Aperture — a Correction „ 120 



Low Powers of Large Aperture „ 120 



Gundlach's Romogeneous-immersion Objectives „ 120 



Secure Method of Setting the Front Lens of Oil-immersion 



Objectives. (Figs. 12-li) „ 121 



New Homogeneous-immersion Fluid of 1-5 Refractive Index „ 123 



Bausch and Lomb Optical Company's Slide-holder .. .. „ 124 



Beck's Rotating Holder for Rubber-cells. (Fig. 15) .. .. „ 124 



Wallis's Calotte Substage. (Fig. 16) „ 125 



Centering Nose-piece as a Substage. (Figs. 17 and 18) . . „ 125 

 Mayall's Spiral Diaphragm for Oblique Illumination. 



(Fig. 19) „ 126 



High Amplifications v 127 



Highest Magnifying Powers ,, IBO 



Origin of Homogeneous Immersion ,, 131 



The Essence of Homogeneous Immersion. (Figs. 20 and 



21) „ 131 



' The Northern Microscopist ' „ 134 



Holman's Compressorium and Moist Chaniber. (Figs. 25 



and26) ,. 142 



Holman's ''Life Slides." (Figs. 21-22) „ 143 



ToUes's Opaque Illuminator for High Powers „ 149 



fl54 



The Apertures of Microscope Objectives. (Figs. 31-35) .. „ i 



The Microscopic Limit, and Beyond. {Presidenfs Address) Part 2 180 

 On the Conditions of Orthoscopic and Pseudoscopic Effects 



in the Binocular Microscope. (Figs. 36-38) .. .. „ 203 



Griffith Club Microscope. (Figs. 39-4:1) „ 293 



Swift's Student's Microscope (Wale's Model). (Figs. 



42-44) » 296 



Abbe's Stereoscopic Eye-piece. (Fig. 45) „ 298 



Watson's Mechanical and Rotating Stage. (Fig. 46) .. „ 300 



" Butterfield " Gauge of Screw for Objectives. (Fig. 47) . . „ 301 



Homogeneous-immersion Objective with extra Front Lenses „ 301 

 Murray and Heath's Polarizing Apparatus. (Figs. 48 and 



49) „ 302 



