GENEKAL MICROSCOPY 



colors in the image to promote visibility and The universal microscope is designed foi 

 rendition of contrast photographically. photomicrography as well as for viewing. 

 It was stated that all components of the This is essential since the microscopist'a 

 illuminating and microscope system should recorded data are in the form of written 

 be centered to obtain good alignment; how- observations and photomicrographs. The 

 ever, this is not always true. Sometimes it Leitz Ortholux is a typical microscope of this 

 is advisable to illuminate the specimen type. It may be attached to the Aristophot 

 obliquely. Several condensers are provided II photographic camera. This camera is 

 with centerable aperture diaphragms, which equipped with a reflex housing which facili- 

 when decentered, direct light at an angle tates the composition and focusing of the 

 onto the specimen. The effect of optical image prior to taking the picture, and in- 

 shadowing is thus achieved. eludes the conventional shutter, bellows, 

 Equipping a Microscopy Laboratory, and camera back. The microscope body con- 

 The requirements for equipping an indus- sists of an inclined binocular tube for viewing 

 trial microscopy laboratory are different for and a single vertical ocular tube for photo- 

 each situation. Nevertheless, the authors micrography. The stage, nose pieces, il- 

 hope that the following comments, taken luminators, tubes and condenser rack are 

 from their experience, will be helpful. The attached to the stand by dovetail devices 

 versatile universal research microscope is which make it simple to change setups. The 

 very well suited to industrial application, new Ortholux UAM stand has two illuminat- 

 Interchangeability of parts, freedom of ing systems, one for incident illumination 

 alignment, choice of optics and illuminations and the other for transmitted illumination, 

 impart the flexibility required to examine the which may be used individually or in com- 

 wide variety of samples found in most non- bination. Either illumination may be ar- 

 biological laboratories. Of course, if one ranged for dark- or bright-field, phase- 

 type of sample must be dealt with continu- contrast, fluorescence, polarized-light, etc., 

 ously, it may be advantageous to acquire a studies. 



more specialized instrument. For example, a In addition to the one illustrated, Reichert, 



metallograph is definitely needed in a metal- Zeiss, and American Optical, among others, 



lurgical laboratory. This is a microscope of provide instruments which are somewhat 



inverted design which will accept relatively similar, 

 large polished metal specimens. Metallo- 



graphic examination falls within the ca- Approach to the Problem and Applica- 



pabilities of the universal microscope, but the tions 

 latter is not so convenient to use routinely 



for this purpose. Assuming a reasonable knowledge of avail- 

 One objection to the universal-type instru- able techniques and the operation and 

 ment is that, although various arrangements limitations of the equipment, increased pro- 

 of optics are available, it can be used only ficiency in the field of microscopy can only 

 for one operation at a time. This is not be gained through research experience. In 

 serious when there is only one microscopist, fact, it is difficult to learn otherwise of the 

 and when more become involved, the prob- diverse applications within a particular area 

 lem can be solved by acquisition of another of investigation. Many phenomena, although 

 stand of the same make. At this time, all manifest on a larger scale, actually take 

 the optical components need not be dupli- place on a microscopic scale, and therefore, 

 cated; only those necessary for special are most profitably studied microscopically, 

 problems could be added as indicated. The background, interest, and ingenuity of 



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