102 The Microscope (chap. 0) 



cent dyes or chemicals) applied to the specimen. Even though many 

 ohjects fluoresce naturally, fluorescence can be intensified in them or 

 induced in others by the use of fluoro( hromes which are simple to use. 

 As with all ultraviolet preparations, nonfluorescent solutions, mounting 

 media and oil immersion must be used. Quartz slides and cover glasses 

 can be used, but are not essential for the technics included in this 

 manual. 



APPARATUS REQUIRED FOR FLUORESCENT MICROSCOPY 



Fluorescent microscopes can be purchased from several of the optical 

 companies [Reichert, Zeiss-Winkel, American Optical). In addition to 

 a compound microscope with a focusable condenser [Abbe is satisfac- 

 tory) minimum equipment includes: a mercury lamp and filter and 

 yello^v check filters for each ocular eyepiece. Although some technicians 

 feel that a front surfaced aluminized mirror should be used, this is 

 not essential. A monocular microscope gives a brighter image than a 

 binocular microscope. 



AMERICAN OPTICAL EQUIPMENT 



1. A mere-Arc illuminator (lamp housing and optics are separate from 

 the power supply), complete with glass optics. Osram HBO-200 lamp 

 and po^ver supply. 



2. Multiple filter holder for use with the illuminator. 



3. Exciter filter for higher light transmission (between light source 

 and microscope condenser) . 



4. Barrier (check) filter for ocular. 



ZEISS SMALL EQUIPMENT 



1. Lighting unit: lamp housing, transformer, mercury burner Osram 

 HBO 74, Schott BG 12 filter, and gives ultraviolet in 350 m/x — 450 

 m/x ranges. 



2. Barrier filter (OG 5) for eyepiece. 



ZEISS LARGE EQUIPMENT 



1. Osram HBO 200 lamp (4| times brighter than above), 2 Schott BG 

 12 filters. 



2. Zeiss OG 4 and OG 5 filters for eyepiece. 



Keep all equipment free from grease, which is opaque to ultraviolet 

 light. 



Fluorescent microscopy differs from ultraviolet microscopy in that 

 the former observes the specimen directly by innate autofluorescence or 



