[Illustration: A MISSISSIPPI RIVER STERN-WHEELER] Capetown is less fortunate in its harbour than Rio, for Table Bay, upon which Capetown is situated, is twenty miles wide at its entrance and is fully exposed to the north and northwest gales. This handicap necessitated the construction of huge breakwaters which enclose two basins of a total area of about seventy-five acres. In addition there is a good anchorage in the lee of one of the breakwaters, and the port is expanding in order to utilize this protected spot. Here again the several miles of quays are of the European type. Marseilles, on the other hand, can hardly be said to have a harbour at all. It is situated on an indentation of the coast which is slightly protected by Cape Croisette, but which is entirely unprotected from the west. This has necessitated the erection of a breakwater parallel to the shore line behind which are a series of basins in which are a dozen or so docks and quays. The Mediterranean is practically tideless, so the basins at Marseilles do not require locks, but the basins, in almost every respect, except for the absence of dock gates, are similar to those, for instance, at Liverpool. A glance might suggest that Marseilles would be an inefficient port, but the contrary is the case. I could go on almost indefinitely listing ports that differ as greatly from these as these differ from one another, but I could hardly show more clearly how diverse are the problems to be solved by the designers and builders of ports. There are many books, of which “Ports and Terminal Facilities,” by Roy S. MacElwee, Ph. D., is one, that discuss the numerous economic, engineering, and structural phases of ports, and to these I refer the person interested in the technicalities of port design, construction, and operation. This outline, being consciously non-technical and limited, must pass on to other things. What is most obvious to the casual observer at a busy port is the great and varied stream of shipping that seems for ever on the move. For a moment I shall turn to this collection of ships in order to explain the uses of the different types and the necessity for them. A ship arrives in a busy port from a foreign country. The ship is large and is designed so as to be easily handled at sea. She is not, however, easy to handle in the restricted and crowded waters of a port. It takes a quarter- or a half-mile circle for her to turn around in, if she is under way, and she is not entirely to be trusted if the tide catches her in narrow waters. A collision may result, and so there are tugboats which, among their numerous duties, are employed to tow her about the harbour, or to assist in turning her, or to push her awkward nose across the sweep of the tide in order that she may enter a dock or swing into a narrow slip. [Illustration: A MODERN VENETIAN CARGO BOAT