482 



Reflection of Light. 



No. 53822 



53 823. 1 : 6. 



53826. 1:5. 



53 827. 1 : 5. 



50. 0. 



53 822. Large Reflecting Goniometer with circle 230 mm diameter, with concealed graduation 

 on silver, objective aperture 31 mm, reading by magnifying glass with 2 verniers for 

 10 seconds, with Centering Apparatus 



The circle and observing telescope have independent motion about the central axis, with screw 

 motion. The measurements can be taken either by firmly clamping the circle carrying the crystal, 

 and by turning the alidade along with the telescope, or by clamping the alidade with the telescope 

 and rotating the circle with the crystal. The instrument has two oculars and a number of slots for 

 the collimator; the observing telescope is provided with an extra objective, thus facilitating the focussing 

 of the objects under test. Illustration on application. 



53.823. Reflecting Goniometer, can also be used as a Spectroscope, K i g u r e, with circle 

 150 mm diameter, concealed, on silver, with reading by means of magnifying glass 

 to 20 seconds; objective aperture 27 mm. Without Centering Apparatus 



53.824. Reflecting Goniometer for the Laboratory, with circle 150 mm diameter, graduated | 

 in l / 3 , with telescope having an objective aperture of 22 mm, with magnifying glass, 

 reading to 30 seconds. Without Centering Apparatus 



27.10.0 



53,825. Centering Device for the crystals, fitting the two preceding goniometers 



19.0. i) 

 3. in. o 



53.826. Reflecting Goniometer, smaller, without magnifying glass reading. Fig. 53,826, prac- 

 tical model for laboratories; telescope of 19 mm aperture, graduated in '/2 an 'l w ' fn 

 vernier for reading to 1 Minute 13. o. o 



53.827. --idem, Figure, with concealed Divided Circle and 2 magnifiers for reading, 

 without prism illustrated in figure 1<>. 0. o 



This pattern can be highly recommended as tl,<> graduation cannot lir touched by the fingers. 



53.828. Model of a Mirror Sextant, of wood, Figure 2. 0. 



Contact Goniometers and Survey Goniometers: sec p. :>-'!>. 



Cl. 5081, 



1248. l-'l'.i. 



