prompt and efficient aid might surely be expected from them. And they had strong motives for doing their utmost to save the last remnant of the Greek Empire. As great commercial communities, they had a direct interest in preserving for the Greeks the city which, as the principal depot of Eastern trade, was one of the main sources of their own wealth. It must, one would suppose, have been well worth their while to have strained their resources to the uttermost for the defence of Constantinople. Something indeed they did, but it was small compared with what by vigorous united action, and in the absence of jealousies and misunderstandings, might certainly have been accomplished. The decisive success which a small Genoese squadron achieved against the entire Turkish fleet during the siege, seems to imply that the will was wanting rather than the ability. Venice and Genoa might well, we are tempted to believe, have saved the city. That with the aid of the Western powers they could have done it, hardly admits of a question. But the aid was not forthcoming, and we have seen some of the reasons why it could not easily have been rendered. At the same time it was absolutely certain that Constantinople must fall without such aid, if the young sultan who succeeded Amurath was both able and aggressive.
Left to its own resources, the city was comparatively weak. Its defences had the reputation of being all but impregnable, and as a matter of fact they proved extremely formidable to the assailant. Phranza describes the landward defence as consisting of two walls, twenty-
