Excerpt from Microscopy in the Service of Man Looking at a microscope, we may recognise a useful separation into two sets of parts, Optical and mechanical, or, if we like, glass parts and brass parts. The glass parts do the work, so to speak, of the instrument, the brass parts make possible their working. The total height of the instrument on Fig. 1 is about a foot. We begin with the optical parts. There are three of these, eyepiece, objective and condenser, naming from the top downwards. (it will be noticed that in Fig. 1 there are two objectives shown, one in position, the other ready to be used when needed.) About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.