188 



L. CASELLA'S CATALOGUE 



FIG. 2186. 



FIG. 2204 



2197. Treble Barrel Air Pump, with two upright and one single barrel as 

 No. 2196, on high mahogany stand, 12-irch. plate with barometer gauge, 

 syphon gauge and key . . . . : . 35 



The gauges having the mercury boiled in them and absolutely deprived of air, these pumps 

 will exhaust them to l'20th inch at a temperature of 60, or l-40th at lower temperatures, a 

 degree of perfection but seldom obtained in pumps of the ordinary construction, at much 

 greater cost. 



Larger pumps with fly-wheels or other modifications made to order. 



PNEUMATIC APPAEATUS, in sets, by means of which with either of the pumps, 

 the whole action of air, with its wonderful influence of 151bs. pressure on 

 every square inch may be demonstrated 



2199. Set of Pneumatic Apparatus, for performing a number of interesting experi- 



ments, consisting of air-pump with 6-inch, sloping barrel, 4f-inch. ground 

 plate on mahogany stand, upright open receiver with glass plate to make it 

 close when required, bladder and hand glass, skin balloon, fruit and taper stand 

 and mercurial cup and saucer, in case complete *'"-*.' . 2 10 



2200. EDUCATIONAL SOCIETIES' SET OF PNEUMATIC APPAEATUS (larger size), con- 



sisting of air-pump on mahogany stand, with sloping barrel 1^ inch diameter 

 and 9 inches long, 5^-inch. brass plate with stop-cock to retain the vacuum 

 when separated from the stand, so as to answer for a transfer or fountain 

 plate, brass table clamps, bell-shaped and open receiver with glass plate, brass 

 fountain jet, glass jar, Mad'geburg hemispheres with handles and stand, 

 bladder glass, bladder frame w ith lead weights, filtering mercurial cup and 

 saucer, guinea and feather apparatus, fruit and taper stand, stand for egg 

 experiment, bulb-tube and glass, glass balloon and car, in case, complete 



6 6 



SYRINGES, WITH FEMALE SCREWS AT THE END. 



If with stop-cocks, 3s. each extra. 



2203. EXHAUSTING SYEINGE, 6-inch, barrel, f-inch bore, 5s. 6d. ; ditto 8-inch, barrel, 



H-inch. bore, 12s. 6d. ; ditto 9-inch, barrel, If-inch bore . 150 



2204. Exhausting and Condensing Syringes, with clamp and cross-piece (fg. 2204), 



to screw to a table or board, 6-inch, barrel, f-inch. bore, 17s. 6d. ; ditto 8-inch. 

 barrel, l|-inch. bore . . . . . . 160 



