All parts of the apparatus are open to the air, and the mercury in the manometer is adjusted so as to come to a fixed mark a.
The substance is now placed on the support already mentioned, and the apparatus closed to the air by inserting the cork at D and turning the cock C. By turning or withdrawing the support the substance enters the bulb; and during its vaporization the free limb of the manometer is raised so as to maintain the mercury at a.
The "receiver" must be connected on the one side to the condenser, and on the other to the exhaust pump. A safety vessel and a manometer are generally interposed between the pump and receiver.
The vaporizing bulb A has fused about it a jacket B, provided with a condenser c. Two side tubes are fused on to the neck of A: the lower one leads to a mercury manometer M, and to the air by means of a cock C; the upper tube is provided with a rubber stopper through which a glass rod passes - this rod serves FIG.
All attempts to dispense with a lead and line and to measure the depth by determining the pressure at the bottom have hitherto failed when applied to depths greater than 200 fathoms; a new hydraulic manometer has been tried on board the German surveying ship " Planet."
Physik, 1906, 21, p. 131) compared the indications of Wien's resonator manometer with those of V.