ON PHYSICAL AND ENGINEERING FEATURES OF THE MERSEY. 965 
vated in the solid rock at Herculaneum Dock, to which reference has been 
made, and which afforded thoroughly safe accommodation for 60,000 
barrels, extensive provision for the storage of petroleum in bulk has been 
made by the erection on some of the undeveloped land at the southern end 
of the Liverpool Estate of a group of five tanks, varying in capacity from 
2,000 to 3,009 tons, and having a total capacity of 12,500 tons. 
They are supplied from the ocean-going tank vessels, berthed alongside 
the west quay of the Herculaneum Dock, the connection being by means 
of pipes through which the oil is forced by the ships’ pumps. Precautions 
against fire are taken, and each tank stands ina moat of capacity sufficient 
to hold the whole contents of the tank in case of accident. Railways are 
laid in connection with each installation. 
At Birkenhead, on land belonging to the Dock Board, there are large 
depots for the storage of petroleum in bulk close to the docks. They 
belong to the Anglo-American Oil Company, Limited, and have a total 
capacity of 18,000 tons. Precautions against fire, similar to those at the 
Liverpool depét, have been adopted also in these cases. 
Extensive warehouses for the storage of ordinary goods, also for the 
special storage of tobacco, have been erected in various positions along the 
Estate, the aggregate floor area of which is about ninety acres. Improved 
buildings of an extensive character for the storage and display of wool 
and tobacco are now in course of erection, from the designs of Mr. A. G. 
Lyster. 
q The Timber Trade of the Port is located at the north end of the 
Estate, where large areas are occupied as storage ground and enclosed 
ards. 
. The handling of the immense quantities of goods of all sorts in their 
transit across the Dock Estate is a very important matter, but scarcely 
more than a passing reference to the appliances required for this purpose 
and for working the bridges, gates, capstans, &c., can be given, It may 
be said, however, that in addition to a large amount of machinery worked’ 
by hand-power, and to the steam-power available on the steamers now 
forming the great majority of the sea-carriers, there are provided by the 
Dock Board a large number of steam and hydraulic cranes, including a 
100-ton hydraulic crane, and a 90-ton steam crane, fixed on dock quays, 
a floating steam crane capable of lifting 100 tons under certain restrictions, 
and any load up to 30 tons freely, and another floating steam crane of 
25-ton power. For the maintenance of the docks, and River channels, 
a large fleet of dredgers of all types, and hopper barges for carrying 
dredged material to sea, are provided. 
Hydraulic power is largely made use of for working bridges, gates, 
capstans, &e. ; centres of hydraulic power being established at a great 
many different points at Liverpool and Birkenhead. 
The means of communication between the Dock Estate and the 
adjoining Towns, and between the several parts of the Estate itself, for 
goods and people, are various and ample. 
The development of the City of Liverpool has steadily kept pace with 
that of the docks, and the interchange of traffic between them is carried 
on by means of a wide street traversing the whole length of the Estate 
from north to south, upon which the side streets abut. This thorough- 
fare is of sufficient width to allow of a double line of railway being laid 
along its margin throughout, communicating, where necessary, with lines 
along the dock quays, and also with several railway systems, which have 
