



The following was extracted from E. J. Spitta : Microscopy, The Construction, Theory, and Use of the Microscope, 1920
Swift & Son's Portable Histological Microscope (Fig. 202) of great excellence. Although primarily designed for the stud of Histology, it is perfect as an all-round instrument. It has the peculiar feature first of having four legs, and secondly of being collapsable, for it can be packed away in the smallest mount of space imaginable, although a little practice is necessary to do this, as a study of Fig. 203 will lead the reader to understand. It may therefore claim admission into the class of Portable microscopes. Constructed for the short tube, it can be extended for. an optical tube-length of 10 in., which makes just a trifle too short for the convenient and scientific use of long-tube objectives, without an additional draw-tube or the use of Zeiss "sliders" or a revolving nosepiece, either of which increases the length sufficiently.