Perhaps half the commerce of Mars, except that in metals and agricultural produce, depends on this post.
Purchasers of standard articles describe by the telegraph-letter to a tradesman the exact amount and pattern of the goods required, and these are despatched at once; a system of banking, very completely organised, enabling the buyer to pay at once by a telegraphic order.
When Esmo had finished his business, we walked down, at my request, to the port.

Around three sides of the dock formed by walls, said to be fifty feet in depth and twenty in thickness, ran a road close to the water's edge, beyond which was again a vast continuous warehouse.

The inner side was reserved for passenger vessels, and everywhere the largest ships could come up close, landing either passengers or cargo without even the intervention of a plank.

The appearance of the ships is very unlike that of Terrestrial vessels.

They have no masts or rigging, are constructed of the zorinta, which in Mars serves much more effectively all the uses of iron, and differ entirely in construction as they are intended for cargo or for travel.