288 Report on the Trials of Reaping Machines at Leamington, 
The " Pulsometer " Steam Pump, of Messrs. Hodgkin and 
Neuhaus, of 61, Queen Victoria Street, London (No. 5645), i: 
an improvement upon the old principle of Savery's engine, in 
which water is raised by being expelled from a close vessel by 
the direct pressure of steam upon its surface, the vessel being 
refilled by condensing the charge of steam. In the " Pulso- 
meter " (Hall's Patent), however, the condensation of the steam is 
effected, not by cooling the vessel either by an external shower or 
internal injection, but by causing the steam to come into sudden 
and intimate contact with the surface of the water after it has 
been depressed to a low level in the chamber. The action will 
be understood from the accompanying drawing (Fig. 11), which 
is a vertical section through the two chambers of the pump. 
Fig. 11. — Vertical Section of Messis. Hodgkin and Neuhaus' 
" Pidsometer " Steam Pump. 
