CHAPTER II.
DEVELOPMENT OF THE OBJECT PICTURE IN THE CASE WHERE OBJECTS ARE DISPOSED UPON A SINGLE OPTICAL PLANE.
SECTION I. Macroscopic Objects : Introductory—Apparatus required for the subjoined experiments—Arrangements for obtaining the different types of illumination required for the development of the outline and object picture—Experiments on the production and effacement of outlines—Deductions from the above experiments—Manner in which outlines are produced and effaced Influence exerted by the refractive index of the enveloping medium upon the development and suppression of outlines.
SECTION II. Macroscopic Objects : Introductory—Method of making the apparatus required for the subjoined experiments—Experiments with glass spherules and cylinders—Experiments with blood films—Comment on the above experiments—Experiments with stained blood films—Influence exerted by the refractive index of the enveloping medium upon the character of the object picture.
SECTION I.
EXPERIMENTS ON THE DEVELOPMENT OF THE OBJECT PICTURE IN THE CASE WHERE THE OBJECT IS VIEWED BY THE UNAIDED EYE, AND EXPLANATION OF THE MANNER IN WHICH OUTLINES ARE RESPECTIVELY PRODUCED AND EFFACED.
1. Introductory.
The conditions of visibility being, as we shall see as we go along, precisely the same in the case of the smallest objects made visible by the microscope as in the case of objects which can be seen by the unaided eye, we may conveniently begin by studying the conditions under which the object picture is produced in the case of such macroscopic objects.
2. Apparatus required for the subjoined experiments.
Cylinders and spheres of coloured and uncoloured glass will furnish convenient objects for experimentation. They will serve in some sort as prototypes of the coloured or uncoloured microscopic elements which are studied by the histologist and bacteriologist
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