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Beck Barnard ultra-violet microscope. Complete outfit. 
Approx. 4 size. 
Fig. 1 shows a bird’s eye view of the apparatus with its screens and camera removed. It 
consists essentially of four parts :— 
(A) A massive iron bedplate (A, Fig. 1). 
(B) The microscope (Figs. 2 and 3 and B, Fig. 1). 
(C) The optical bench for illumination with visible light (C, Fig. 1). 
(D) The optical bench for ultra-violet illumination (D, Fig. 1). 
(A) The main bedplate is a heavily ribbed iron casting of great strength and rigidity. The 
microscope is placed at its narrow end fitting into three slots, which accurately locate the three 
toes of the microscope (B, Fig. 1) and thus its accurate alignment with the rest of the apparatus 
is ensured. The two optical benches (C and D) are fixed to the main bedplate. This bedplate is 
supported on three feet. A series of tapped holes (e, Fig. 1) are provided, into which pillars are 
screwed, to support screens to enclose the illuminating apparatus. 
(B) The microscope is illustrated in Figs. 2 and 3. It consists of an iron casting (f, Fig. 3) 
of great rigidity which stands on three toes. Upon it are two dovetail slides (g and). The slide (g) 
carries the focussing unit (k) and the slide (/) carries the substage (j). Running in a slide in the 
casting and below the slide (g) is a long bar (/). It carries an adjustable bracket (mm) to support 
the fluorescent eyepiece (v) with provision for accurately aligning it with the main eyepiece. 
The bar is provided with a clamp. The stage (0) is supported on a massive bracket (f') which is 
part of the main casting. It is held down upon an accurately flat surface fitting on three small 
raised areas by three springs. A very accurate lateral motion of about 1] cm. in each direction 
is imparted to the stage by means of the adjusting screws (fp). The slide holding the object consists 
of a quartz slip-5 m/m. thick, and a fused quartz cover glass is used. The slide is held on the 
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