PORT ECONOMICS 
though logs are often stored in timber ponds until 
required. Conveyors have been devised for the work of 
unloading deals and planks, but they lack the discrimina- 
tion of the human intelligence in regard to marks. 
CARGO APPLIANCES 
While it has been shown that the operations of dis- 
charging and loading are very largely in private hands, 
and although the port authority may not be directly 
interested in such operations, yet it is universally recognized 
that it devolves upon a port authority to equip its docks 
and quays with adequate appliances for handling cargo. 
These appliances are principally cranes, which are let on 
hire on a time basis and may be engaged as desired. There 
is no compulsion, or even necessity, to hire a port 
authority’s quay cranes, when a ship is sufficiently equipped 
(as indeed most are) with its own booms, whips and 
tackle. But quay cranes are a useful appendage, and can 
be used in conjunction with the ship’s equipment and also 
to supplement it. 
As the most outstanding port appliance for cargo 
handling purposes, the Quay Crane merits some brief 
notice. It has certain special features which differentiate 
it from the ordinary type of land crane. On account of 
having to clear the lofty bulwarks of a vessel in the light, 
or unloaded, condition, and also for the purpose of 
enabling the crane driver to command a view of his work, 
it is generally mounted on a pedestal, which takes the form 
of a framed substructure, mounted on a wheel base, and 
designed to allow of the passage of railway stock between 
its side supports and under its platform. The crane arm, 
or jib, has generally a considerable outreach in order to 
enable it to plumb the hold of a vessel which may have a 
barge lying between the vessel and the quay. And, in 
order to avoid collision with the yards and stays of shipping, 
the jib is fitted with a luffing motion, which enables it to be 
moved forward and backward in a straight line, in addition 
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