Page:Principles of Microscope.djvu/38



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.

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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