ve PORT ECONOMICS 
work carried on at different quays. It would serve no 
useful purpose, for instance, to institute a comparison 
between the tonnage of coal and the tonnage of sacked 
or bagged goods, because they are handled in totally 
different ways and a much greater rate of speed is attain- 
able in one case than in the other. But berths assigned to 
the same class of goods—even so wide a range as is com- 
prised in the term General Goods—may be contrasted with 
useful results. Where there is a discrepancy in two cases, it 
may be that delays are caused in one case by insufficient or 
ineffective appliances, a defect which is quite remediable. 
INDUSTRIAL ZONES 
Some port authorities find useful sources of revenue 
arising from the letting of sites for industrial purposes; 
indeed, the establishment of industrial zones in the 
immediate vicinity of a port is a distinctive feature of 
modern lay-out, it being recognized that such zones serve 
as feeders to the business of the port and foster its develop- 
ment. At the same time, they should not be allowed 
to occupy valuable frontage space, but should be located 
a little in the background, with such rail, road and water 
communication as is desirable and necessary. There is a 
considerable area of this kind under development at 
Trafford Park, Manchester, adjacent to the Manchester 
and Salford Docks, where, in addition to an important 
group of warehouses and stores, a large number of works 
and factories are springing up. A similar project is in 
course of materialization at the new port of Venice—the 
Industrial Port, as it is termed—located on the mainland 
and connected with the ancient port by a channel across 
the lagoon. Other instances might be adduced, but the 
advantage of the arrangement is obvious. 
FREEPORT AREAS 
These industries and factories may be established in 
connection with those port areas which are known as 
KR