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CONTENTS 
Micrometry by means of a scale projected by the Abbe condenser. 
Use of the micrometer fine adjustment. 
Measurements of thickness. 
Practical applications of micrometric measurements. 
CHAPTER VIII. 
Quantitative Analysis by Means of the Microscope. 
Methods available. 
Analysis of powdered material. 
Net ruled oculars and their uses. 
Counting cells. 
Sampling.. 
Determination of weight by micrometry. 
Volume and weight per cents; area measurements. 
Estimation of molecular weight. 
Micro-colorimetry. 
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CHAPTER IX. 
The Determination of Melting and Subliming Points. 
Approximate methods. 
Exact methods. 
Hot stages. 
Subliming points. 
CHAPTER X. 
The Determination of Refractive Index by Means of the Microscope. 
The relation between refractive index and contour bands 
Principle of the immersion method. 
Behavior of air bubbles and oil globules. 
Half-shadow method of illumination. 
Refractive index of anisotropic crystals. 
Uniaxial and biaxial crystals. 
Determination of the refractive index of liquids. 
Determination of thickness by refractive index. 
Liquids for use in the immersion method. 
Crystals for use in the immersion method. 
Refractive indices of typical crystals. 
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CHAPTER XI. 
Crystals under the Microscope. 
Fundamental principles of crystallography. 
Elements of optical crystallography. 
