12 REPORT—1848. 
distance of about sixty miles by a series of nine pressure-engines, acted upon 
by falls of water from the hills, and each of them working a pump. 
A description of these engines will be found in the Proceedings of the 
Institution of Civil Engineers, and an excellent drawing, by Mr. W. L. 
Baker, of one of the best engines of the series, constructed by M. de Reichen- 
bach, will be found in the collection of that institution. This engine has a 
cylinder of twenty-six inches in diameter, with a stroke of four feet, making 
in regular work five strokes per minute; it is made entirely of brass and is 
an excellent machine, both in design and workmanship. Very few working 
parts are visible, and it acts almost without noise; the sliding valves, or 
rather sliding pistons, which regulate the engine’s action, being also moved 
by water-pressure. 
The other example, at Freyberg in Saxony, is an engine constructed by 
MM. Brendel in the year 1824, for draining the Alte Mordgrube mine. It 
has two single acting cylinders attached to opposite ends of a working beam 
by means of arched heads and chains; the cylinders are open at top, and 
have strong piston-rods of timber. The pressure of the water acts alter- 
nately under the piston of either cylinder and forces it upwards, whilst the 
piston of the cylinder at the other end of the beam is depressed by the 
weight of the pump-rods. A bell crank attached to each piston-rod gives 
motion to the pump-rods, each working twenty-two pumps, placed one above 
the other, lying at an angle of forty-five degrees, and dividing the lift of each 
set of pumps into twenty-two heights or stages of about thirty feet. The 
engine is placed 360 feet underground. The cylinders are of cast-iron, 
eighteen inches in diameter, with a stroke of nine feet; and the useful effect 
was computed by M. von Gerstner to be seventy per cent. of the power ex- 
pended. A section of one of the cylinders, showing the mode of working the 
valves, has been sent me by a friend at Wiesbaden, and an excellent drawing 
of this engine by Mr. Baker will be found at the Institution of Civil Engineers. 
The first water-pressure engine used in England was erected by Mr. Wil- 
liam Westgarth, at a lead mine belonging to Sir Walter Blacket, in the 
county of Northumberland, in the year 1765. 
The cylinder of this engine was equal in length to the whole height of the 
fall of water; it was open at the top, and the water ran into the open top of 
the cylinder by a trough; the piston worked in a bored chamber, at the 
lower end, of ten inches in diameter, and was attached by a chain to the 
arched head of an engine beam placed above, the opposite end of the beam 
suspending a wooden rod, which passed down the pit to work the pump. 
The column of water always pressed upon the top of the piston, but by 
admitting water below the piston the pressure was neutralized, and the 
- piston was raised by the weight of the descending pump-rods. On closing 
the communication with the underside of the piston and discharging the 
water from the cylinder bottom, the pressure of the column again acted 
upon the piston and sent it down. By a simple and self-acting piece of me- 
chanism, similar to the working gear of the steam-engines of that time, the 
orifices were alternately opened and shut, and the reciprocating motion of 
the engine continued. 
A detailed account, with drawings of this engine, was submitted to the 
Society of Arts in the year 1769, and printed in the fifth volume of the 
Society’s Transactions in 1787. The description and drawings, from which 
a model was then made, were given by Mr. Smeaton: the Society voted fifty 
guineas to Mr. Westgarth, and presented a silver medal, with their thanks, to 
Mr. Smeaton for his excellent account of so valuable an invention. 
I have carefully examined these interesting memorials of the early encou- 
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