414 



CENTRAL SCIENTIFIC CO., CHICAGO, U. S. A. 



No. 10936. No. 10938. 



No. 10962. 



No. 10984. No. 10986. 



No. 10990. 



No. F2217. 



10936. POTASH BULB, Wetzel-Geissler, with drying tube attached by rubber tubing... $2.50 



10938. POTASH BULBS, Winkler, spiral form. No A B 



Height, mm 100 180 



Bach 2.00 2.50 



10942. POTASH BULB, Zahradink, with drying tube ground on. Convenient to use as it stands easily 



on its own base 3.00 



For other POTASH BULBS, see Absorption Bulbs and Tubes. 

 POTASH BULB SUPPORTS, see Supports. 

 10946. POTATO CUTTER, Ravenel, for cutting potato cylinders 18 mm in diameter and halving them 



at the same time 2.00 



PRECIPITATING JARS, see Jars. 

 PRESS, Filter, see Filter Press. 



2400. PRESS, Pellet, for use in calorimetric determinations for briquetting powdered fuels.... 20.00 

 10962. PRESSES, Tincture, extra heavy, for making tinctures, extracts, etc. 



Capacity, quarts 1 2 4 8 



Each 2.00 2.50 4.00 6.00 



PRISMS, see Catalog F of Physical Apparatus. 

 PROJECTION APPARATUS, see Catalog F of Physical Apparatus. 

 PROOFING CABINETS, see Flour Testing Apparatus. 

 PSYCHROMETERS, see Hygrometers. 



F2217. PULSE or PALM GLASS, Franklin's. Two glass bulbs with connecting tube, containing water 

 and water vapor. When one bulb is held in the hand, the warmth of the hand is sufficient 

 to cause rapid evaporation of the water, thus causing sufficient pressure to force the liquid into 



the other bulb, where a rapid boiling occurs. About 18 em long .65 



PUMPS, Acid, see Acid Pumps. 



PUMPS, Air, Blowers, see general heading Blowers. 



PUMPS, Air, Filter, see Filter Pumps. 



AIR PUMPS, COMPRESSION AND VACUUM 



10980. PUMP, AIR, Compression. A so-called hand bicycle pump 13.5 cm long by 2 cm in diameter .50 



10984. PUMP, AIR, Vacuum and Pressure. Cylinder is of heavy brass, nickel-plated, 40 cm long by 



54 mm in diameter. A vacuum to 29 ] /^ in. may be obtained by use of this pump. Mounted on 



an oak base 15.00 



10986. PUMP, AIR, Vacuum and Pressure. Useful in elementary work in the laboratory and where only 



a partial vacuum is desired. Cylinder is of brass, 28 cm long by 2.5 cm in diameter. Mounted 

 on stirrup for ease in using 4.50 



10987. EXTRA VALVE for No. 10986 Air Pump 05 



For PUMP PLATES, see page 416. 



10990. AIR TANK, for use especially with Nos. 10984 or 10986 Air Pumps. A 12 liter air tank with a 

 30 Ib. pressure gage mounted on a nicely finished hardwood base. For convenience in mov- 

 ing from place to place the support is provided with a handle and an air drying tube is mounted 

 on one of the uprights as shown in the illustration. This apparatus may be used where air un- 

 (lor pressure is needed, e. g., for driving stirrers in chemical laboratories. With stopcock at both 

 air inlet and air outlet and with rubber tube for connection with Nos. 10984 or 10986. . 20.00 



