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The practical advantages to be derived from the use of the 
hydrostatic crane, are : — 
1. The great economy of the power employed, which, it 
must be remembered, is steam poicer, the water being merely 
the vehicle by which the power of the engine is transmitted. 
2. The applicability by this means of steam power to 
small cranes. 
3. The facilities it presents for working a whole system of 
-machinery, however widely scattered the different machines 
composing that system may be, from one engine in any con- 
venient locality. 
4. The small amount of room upon wharves taken up by 
hydrostatic cranes. 
5. The great speed at which such cranes can be worked 
with small loads, a speed utterly unattainable by the manual 
crane. 
From some experiments I made upon the cranes at 
Grimsby, I believe that in the case of any article which can 
be cleared from a ship's hold with sufficient rapidity, 500 tons 
per day of ten hours might be discharged, at a cost of one- 
third of that doing the same amount of work by the manual- 
power crane. In one establishment, indeed, the cost was 
reduced from 3d. to per ton by the use of the hydro- 
static crane. Cranes are, in fact, now so complete, that little 
more improvement need be made in the rapidity of their 
action, until some methods are found out whereby the loading 
and unloading of vessels and other vehicles can be facilitated; 
as, when the articles are bulky or very heavy, even the 
manual crane remains idle for a considerable part of the time 
occupied in loading or unloading the cargo. 
Hydrostatic machinery can be easily worked from the 
public water supply, if the pressure be sufficient. Its use is 
rapidly extending ; it has been applied to the purposes of 
riveting, moving swing-bridges, turntables, and railway- 
