392 



Motion of Gaseous Bodies. 



No. 



52915. 1:10. 



52 917. 1 : 8. 



s. ,!. 



52.012. Vacuum Pump as No. 52,911, with 220 volt I). ('. Motor 2:;. 5.0 



52.013. - - i d e m, with Plate 240 mm diameter and Barometer Gauge 200 mm high; 110 volt 



D. C. Electric Motor . . . , 26. 0. 



Largest Receiver for use with above: No. 53,013 li. 4. '.I 



52.014. --idem, with 220 volt 1). f\ Electric Motor 25.15.0 



52.015. Duplex Vacuum Pump with Oil-packed Piston and oil non-return valve. Kohl's system, 

 German Patent, Figure, with Hand Lever. 2 Barrels of the same size 50 mm in 

 iuiernal diameter; Stroke 120 mm, for exhausting glow lamps and X-Ray Tubes as well 



as for rapidly obtaining a vacuum, without Plate 17. Hi. n 



52,016. 



- idem, with Plate 240 mm diameter and Barometer Gauge 200 mm high . . 20. 0. o 

 Largest Receiver for use with above: No. 53,013 0. 4. '.I 



52.017. Duplex Vacuum Pump with Oil-packed Piston and oil non-relurn valve. Kohl's system, 

 del-man Patent, with Fly-wheel and Clearing, Figure, for Hand and Motor Drive. 



with 2 Harrels of same si/,e of 50 mm internal diameter; Stroke 120 mm; without Plate 24. Hi. 



Tin- pump e\liau>is to 0.0014 mm. 



To faeililale the working of the Pump, especially when eoiimiencing to pump, we have provided 

 the pump with a toothed wheel gearing, as experience shows that it is much easier lo expend a small 

 amount ol eueruy in turning a wheel SO Km times a minute than to turn ' times a minute 



with fi correspondingly larger amount of energy. Tue cog wheels are cased in. 



52.018. -- idem, with Plate 240 mm diameter and Barometer Gauge 200 mm high . . 27. o. o 



Largest Receiver for use with aliove: No. .Vt. (>]'> . I. fl 



52.'.M>. Duplex Vacuum Pump with Oil-packed Piston and oil non-return valve. Kohl's system, 

 (lermaii 1'alenl, Figure, with Fly-wheel, without gearing; arranged for Hand and 

 .Motor Drive; with 2 Harrels of equal si/e of 50 mm internal diameter; stroke 120 mm; 

 without Plate 22.10.0 



The pump exhausts to 0.0014 mm. 



52.020. - - i d e in. with Plate 240 mm diameter and Barometer Gauge 200 mm 



Largest Receiver for use with ahove: No. .">.'!. Ol.'J ' 



25. 0. 



o. i, '.i 



52.021. - - i d e m, driven by a ' ; ' ' H. P. 110 volt Direct Current Electric Motor. F i g n r e, 



On table with polished oak top and iron frame; without Plate 15. o. O 



The air pump is mounted on a talile with polished oak top and iron frame. The shelf under- 

 neath, as seen in the illustration, carries the ' ,rd [| I>. |>. r. Klccttic Motor fitted with worm 

 The starling rheostat as well as thf necessary Mvilehgear- are mounted on the talile top. 



il. 'Jit, 4712. 



