192 L. CASELLA'S CATALOGUE 



2249. Respiration Glass, illustrating the inspiration, etc., of the lungs 6 



2250. HAND AND BLADDEE GLASSES, mounted for illustrating the pressure and per- 



cussion of the atmosphere . . . 2 and 2 6 



2252. Leslie's Apparatus, for freezing water in a vacuum, with receiver 5 inches 



diameter, 6s. 6d. ; 7| inches . . . . . 12 6 



2253. BELL EXPEEIMENT, for illustrating that air is essential to sound 066 



2254. SLIDING KOD, plate, and collar of leather . 096 and 12 6 



2255. TOEEICELLIAN EXPEEIMENT, with connections and flexible tube 15 6 



2255*. , having the barometer fixed in the cap of the glass 



receiver (the column to descend) . . . . 110 



2256. SYBINGE AND LEAD WEIGHT . . . . . 10 



2257. Pocket Condenser or Fire Syrillge, for instantaneous light, with amadou 



036 



2258. MODEL OF WATEE PUMP, with glass barrel . . . 150 



2259. CONDENSED AIE FOUNTAIN, with syringe and jets, complete . 3 17 6 



2260. MEECUEIAL VACUUM GAUGE . . . . . 036 

 2262. PHILOSOPHICAL OB WATEE HAMMEE . 3 to 5 6 



HYDROSTATICS AND HYDRAULICS, 



Comprising such instruments and apparatus as illustrate the properties of fluids and 

 that part of mechanical science which relates to their forces and motion. 



2263. Hydrostatic Equilibrium Apparatus, showing that fluids will seek and main- 



tain the same level, irrespective of the sizes of the channels through which 

 they rise . . . . . . 1 15 



2264. DITTO, in glass . . . . . . . 046 



2265. HYDEOSTATIC PAEADOX, illustrating the principle, that the smallest column of 



water of a given altitude, will balance one of any size of the same height, 

 15s. to . . . . . . . 1 10 



2266. Hydrostatic Bellows, illustrative of the principle that fluids give equal pressure 



in all directions, the force being proportionable to the perpendicular height of 

 the column of fluid . . . . . 1 15 to 3 3 



2267. BEAMAH'S HYDEOSTATIC PEESS (working model), highly finished to scale, with 



keys and breaking irons, complete to 30cwt. . . 12 12 



An iron bar 6 inches long by J-inch. thick may be broken by it. 



2268. HYDEOSTATIC PEESS (working model), of smaller size, for pressing substances or 



raising weights to 4001bs. . . . . . 660 



2269. HYDEAULIC PEESS, for pressing or lifting, giving a measured gauge pressure up to 



3 tons on the square inch, with pressure plates arranged to order 25 

 Various forms and sizes made to order. 



