xl INTRODUCTION. 



thing like a definite plan. They may also sen^e to refresh the memory of those who are 

 aware that such means exist, but who do not take advantage of them. 



The follomng list of incongruous materials, forming an analysis of the second part of the 

 Introduction, may serve to recal to the observer the most important points to be looked for, 

 and the means of discovering them. 



Microscopic ANALYSIS. Form: — a, outline', b, rolling over ', c, side view ; d, end 

 view ; e, angles, goniometer. 



Colour : — 1, General colour, true colom'; 2, pigment; a, partial from pigment ; 5, general 

 colour from pigment ; 3, iridescence, thin plates ; air-bubbles, &c., immersion in highly re- 

 fractive liquids, action of transmitted and reflected light ; compression ; 4, polarization, &c. 



Sm'face : — Reflected light {Brooke's apparatus) ; projections ; cilia, margin, iodine, desicca- 

 tion, fine particles ; hairs, crystals, upon or beneath the surface; tubercles, ridges, folds, 

 side view ; effects of altered focus ; fracture ; foramina, polariscope ; illusoiy lines, dif- 

 fraction ; depressions, circular, angular ; furrows ; tubules ; cells ; oblique light, stops in 

 condenser. 



Internal stiiicture and contents: — Homogeneous; cell-wall, endosmosis, exosmosis, chlo- 

 ride of calcium ; adherence ; margin, crushing, molecular motion ; granules ; nucleus, 

 central, excentric; reagents, acetic acid; nucleolus, vacuoles. 



Histological analysis. — Reagents; maceration, development. 



Micro-chemical analysis. — Washing; heat; red heat, odour, ash ; reagents, con- 

 tact with reagents j potash, iodine, sulphuric, muriatic, nitric, acetic acids j Millon's test j 

 sulphuric acid and syrup j sulphuric acid and ioditie y (Ether, Sfc. 



Measurement. — In fractions of an English inch (not line nor foreign measures). 



Bibliography. — Optics. Herschel, ' Optics,' Encyc. Metropolitana; Brewster, Optics; 

 Biot, Manuel, ^'c; Ai't. ' Optical Instruments' in Natural Philosophy of the Society for the 

 Diffusion of Useful Knowledge ; Lardner, Natural Philosophy, &c. &c. 



Microscopes, Apparatus, and Observation. Quekett on the Microscope, 2nd ed., 

 1853 ; Brewster, Treatise on the Microscope ; Ross, Axt. 'Microscope ' in the Penny Oyclo- 

 pcedia; Dujardin, Observateur ; Mandl, Traite pratique du Microscojje, Paris, 1839; 

 Cli.evaHer, Traite des Microscopes, SfC, Paris; Tulk and Henfrey, Anatomical Manipulation; 

 Von Mohl, Micrographia (German) ; H. Schacht, Das Microscop (German, translated by 

 Currie, 1853) ; Harting, Het MiJcroskoop (Dutch ; extracts in Edinburgh Monthly Journal of 

 Medical Science, 1852); Carpenter, article ' Microscope ' in the Cyclopcedia of Anatomy 

 and Physiology ; Transactions of the Microscopical Society of Lotidon, and Quarterly 

 Journal of Microscopical Science (passim), &c. &c. 



