£3 PORT ECONOMICS 
considering how the railway lines of a port may be worked 
in conjunction with the quayside services of a port is of the 
utmost importance. 
At all modern docks and quays, wherever it is a 
practicable arrangement, there are laid along the quay 
front two or more lines of rail track for the purpose of 
receiving goods direct from ship, and usually also at the 
rear of the transit sheds, one or more additional lines, to 
receive goods which have been passed through the sheds 
for sorting purposes. 
In England, the wagons on these lines, when loaded, 
are taken to a Dock Exchange Sidings, which is a set of 
sidings consisting of a number of parallel tracks, commonly 
called a gridiron, especially laid out for the reception and 
marshalling of wagons and the formation of trains for 
dispatch. Wagons arrive at these sidings, either loaded 
with material for shipment, or empty for the purpose of 
receiving imported goods, the ideal being, of course, to 
have the wagons laden in both directions. 
The exchange sidings, in the case of British ports, 
mark the stage at which transfer takes place between 
railway operation and dock operation. To and from 
inland stations as far as the sidings, the wagons and their 
contents are under the charge and direction of the railway 
companies. Between the sidings and the quay, the port 
authority assumes control. The practice as to motive 
power is slightly varied. Generally, the port authority 
provide locomotives to haul over their tracks, but some- 
times, the railway companies do the work under arrange- 
ment, and, if they are the dock owners, there is obviously 
no change of control. 
The foregoing represents the practice which is character- 
istic of British port methods. The port authority (unless 
it happens to be a case of docks under railway ownership) 
do not concern themselves with the incoming or outgoing 
traffic, except in the immediate vicinity of the quays. The 
selection of routes, and the convergence or divergence of 
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