Paul Gebhardt, Berlin S. 



147 



No. 2803. 



Paul Gebhardt, Berlin S., 



85 & 53 Prinzenstrasse. 



Mechanician and Optician. 



Established 1870. 



Factory and Ware-house of scientific, physical, electrical, 



optical, mechanical and chemical 

 apparatus and appliances for class-demonstration. 



List of Exhibits: 

 Mechanics: 



System of 2 X 3 brass pullies, with stand and weights. 

 Model of a crane, of metal, with double gear. 

 Hydraulic press with brass cylinder. 



Large double barrelled air- 

 pump (Fig. 1) with Babi- 

 net's cock, glass cylinders 

 and vacuum-gauge. Acces- 

 sories: Barometer test,, 

 dasymeter, Magdeburg 

 hemispheres of brass. 

 Mercury shower with 

 cock and mercury-bottle 

 with screw on stand. 

 Apparatus for demon- 

 strating propagation of 

 sound in vacuum, elec- 

 trical, with recipient, and 

 binding-screws. 



Iron Centrifugal machine, horizontal and vertical, adjustable. Also: 



2 balls of unequal weight. 

 Watt's regulator. 



10* 



