36 Max Kohl, Chemnitz. 



1. Bianchi Air Pump. (Fig. 1.) 

 This pump is double acting and fitted with Babinet cock. 



The 



cylinder being made of glass the piston is protected from oxydation,, 

 which cannot be avoided with metal cylinders. The valves are, in 

 contradistinction to older types, placed outside the barrel and are thus 

 easily accessible for the purpose of cleaning the pump. The air pump 

 is capable of producing an exhaustion of 2 mm mercurial pressure gauge. 

 The plate is fitted with electrodes communicating with the interior of 

 the recipient. 



Fig. 2. 



2. Deleuil Air Pump. (Fig. 2.) 



The metal piston works very easily in the glass barrel. The pump 

 is double acting and may be used both as an exhausting and com- 

 pressing pump. It is capable of producing exhaustion of 2 mm mercurial 

 pressure gauge. 



