Testimonials as to Projection Apparatus. Some Estimates of Cost. 



189 



Cleveland, Ohio, 31st May 1906. 

 The second consignment of apparatus was duly 

 received in perfect order, and all is very satisfactory. The 

 oil air-pump and the Megadiascope are pleasing in the 

 highest degree. 



Dayton C. Miller, 

 Case School of Applied Science, Department of Physics. 



I" n t e r - B a r m e n, 2">th May 1906. 

 I am satisfied with the Megadiascope supplied. 

 Direction der Konigl. Baugewerkschule Barmen-Elberfeld. 



Duisburg-Meiderich, 22 n<1 December 1905. 



(Lower Rhine) 



The Megadiascope has done all that is expected of 

 it m a school lecture. H Hermanni 



Berlin, 15th November 1905. 



In acknowledging the receipt of the spirit glow lamp 

 I am glad to be able to inform you that it entirely fulfils 

 my expectations. It yields a beautiful, bright light, which 

 fully suffices for school purposes. The attention required 

 by same is of a much more simple character than I ex- 

 pected at first. 



Oberlehrer Jost, XI. Realschule. 



K a 1 o c s a, 13th December 1904. 

 I am greatly satisfied with the microprojection outfit. 

 Alexander Riegl, Curator, Obergymnasium. 



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Some Estimates of Cost of Projection Outfits. 



If desired, some special estimates will be prepared to conform to special local conditions. If 

 a different mode of lighting or a different voltage or kind of current are to be used than given, 

 the prices are altered correspondingly. 



Estimates for Outfits with the Megadiascope: see p. 1230. 



Outfit with the School Projection Apparatus, 

 Modell A, tall Form. 



. d. 



o 



5H.735. 1 School Projection Apparatus, Model A, 

 tall Form, for projecting Apparatus and 

 Slides, with 122 mm diameter condenser, 

 achromatic Projection Objective 55 mm 

 diameter and 180 mm focal length, Optical 

 Bench, Change Frame with inset frame for 

 slides 8.5 x 10, 9 x 10.5 and 9 x 12cm plate- 

 size, 1 Stage and 1 adjustable Slider with 

 stand for taking the Change Frame, the 

 Stage or other objects, with an Arc Lamp 

 Hand Regulator, which can be used both 

 for Direct or Alternating Current and for 

 various currents up to 30 amperes . . . 



"in.sTS. 1 Switchboard for connecting the Projec- 

 tion Apparatus up to the Wall, for 30 amps, 

 maximum . 



12. 10. 



1. 10. 



."iu.s(i<). i Series Resistance for 15 amps, in con- 

 junction with 110 Volts Direct Current . 1. 15.0 



~>].<ii.7. 1 Projection Screen 3 x3 m, of prepared 

 pure-white fabric for reflected light, with 

 draw-cord rolling-up device, for firmly 

 fixing to the ceiling 3. 0. 



Cases and Packing for land transit ... 0. 15. 



Total 19. 10. 



In the case of Three-phase or Alternating 

 Current plants a transformer No. 50,880 or 

 50,881 is used instead of the series resistance. 

 Extra price, for 220 Volts Alternating 

 Current . . 1. 10. 



Outfit with Model B Projection Apparatus, having 

 Aluminium House. 



s. n. 



50,790. 1 Projection Apparatus, Model B, with 

 Aluminium House, for projecting Apparatus 

 and Lantern Slides, with 122 mm diameter 

 condenser, achromatic Projection Objective 

 55 mm diameter and 180 mm focal length, 

 with Optical Bench, Change Frame with 

 inset frame for photographs of 8.5 x 10, 

 9 x 10.5 and 9x12 cm plate-size, 1 Stage 

 and 1 adjustable Slider with stand for taking 

 the Change Frame, the stage or other objects, 

 and with an auto-regulating Direct Current 

 Arc Lamp for 15 amps 16. 10. 



50,878. 1 Switchboard for connecting the Projec- 

 tion Apparatus up with the Wall .... 1. 10. 



50,869. 1 Series Resistance for 15 amps, in con- 

 junction with 110 Volts Direct Current 1.15.0 



51,007. 1 Projection Screen, 3 x3 m, of prepared, 

 pure-white fabric for reflected light, with 

 draw-cord rolling -up device, for firmly 



fixing to the ceiling 3. 0. 



Cases and Packing for land transit . . . 0. 15. d 



Total 23. 10. 



In the case of Three-phase or Alternating 

 Current plants, a Projection Apparatus 

 No. 50,791 is used instead of the above 

 called, and a Transformer No. 50,880 or/ 

 50,881 is used in lieu of the abovementioned 

 series resistance. Extra price for same, 

 for 220 Volts Alternating Current. . . 2 .11. o 



