Vacuun\ \mps 



No. 1 Vacuum Pump 



No. 5681 — No. I s '\ 

 shown in cut, 1 '^' . 

 vacua to i/soth of an 

 inch and has a capacity 

 of 4 cubic feet per 

 minute. It requires 1/2 

 H. P. motor. 



No. i-^ size pump is used 

 with No. I to give vacua 

 to i/ioooth of an inch. 

 It requires ]^ H.P. motor. 



No. 2 is used with No. i to give vacua to i/iooooooth of an inch, 

 quires j^ H. P. motor. 



It re- 



Above pumps are compact, and require comparatively little power. 

 They are easy and safe to operate. They are used for X-ray tubes, nitrogen 

 lamps, tungsten lamps, thermosbottles, rectifiers, also for general laboratory 

 and lecture work. 



No. 3709 — Columbia University Model, improved form of McLeod Vacuum 

 Gauge mounted on oak board. This gauge is compact in construction, 

 easy to operate, has no glass joints and is accurate to one ten-millionth 

 of an atmosphere. 



The gauge is recommended for use with above pumps, and wherever 

 exact determinations of vacua are required. 



Write for Bulletin No. 26g 



Columbia 

 Model 

 Gauge 



NEW YORK CITY 

 3rd A«., 18th— 19th St, 



TREnd 



1851 imH 

 PITTSBURGH OFFICE 

 2011 Jackfon Arcade 



