OF HYDEOSTATIC AND HYDEAULIC APPAEATUS. 193 



FIG. 2270. 



2270. HYDRAULIC TESTING APPARATUS (.fa. 2270), 



As expressly constructed by L. CASELLA by desire of the Admiralty, for determining 

 the effect of deep sea pressure on the thermometers employed for testing its 

 temperature ........ 35 



FIG. 1 shows a section of the apparatus, A being a strong cast-iron cylinder about 

 27 inches long by 13 inches wide, a is a hollow receptacle about 16 inches deep by 6 

 inches wide ; b a steel plug of proportionate size ; and d a receptacle through which 

 the steel key d d in FIG. 2 passes to hold the plug down ; the other general arrange- 

 ment is that of the usual hydraulic pump, the water being forced through the con- 

 necting tube m. 



FIG. 2 shows the general end view of the apparatus. 



The pressure to which it is generally used for testing the deep sea thermometers 

 is 2i to 3 tons on the square inch = 2500 fathoms depth in the sea. (See 

 deep sea thermometers, p. 17.) 



2272. fflontgolfier's Hydraulic Ram, in which the velocity of water flowing through 



a long pipe is obstructed, and being connected with a smaller pipe, the column 

 thus reduced is considerably raised .... 4 4 



Hydraulic pressure gauges, see pressure gauges, p. 198. 



2273. ARCHIMEDES SCEEW, consisting of a tube wound round a cylinder revolving 



obliquely, an ingenious and primitive method of raising water, 15s. 6d. to 



1 10 



2274. APPARATUS to illustrate that more water flows from a vessel through a short pipe 



than from a mere aperture of equal size . . . 10 6 



2275. APPARATUS for illustrating the laws by which fluids spout through various jets 



220 and 330 

 O 



