The Tower is in the best situation that could have been chosen for a fortress, it lying only 800 yards to the eastward of London Bridge, and consequently near enough to cover this opulent city from invasion by water. It is to the north of the river Thames, from which it is parted by a convenient wharf and narrow ditch, over which is a drawbridge, for the readier taking in or sending out ammunition and naval or military stores. Upon this wharf is a line of about sixty pieces of iron cannon, which are fired upon days of state.
Parallel to this part of the wharf upon the walls is a platform seventy yards in length called the Ladies line, from its being much frequented in summer evenings by the ladies, as on the inside it is shaded with a row of lofty trees, and without affords a fine prospect of the shipping, and of the boats passing and repassing the river. The ascent to this line is by stone steps, and being once upon it, you may walk almost round the Tower walls without interruption, in doing which you will pass three batteries, the first called the Devil’s battery, where is a platform, on which are mounted seven pieces of cannon: the next is named the Stone battery, and defended by eight pieces of cannon; and the last, called the Wooden battery is mounted with six pieces of cannon: all these are brass, and nine pounders.
But to return to the wharf, which is divided from Tower Hill at each end, by gates opened every morning for the convenience of a free intercourse between the respective inhabitants of the tower, the city, and its suburbs. From this wharf is an entrance for persons on foot over the drawbridge, already mentioned; and also a water-gate under the Tower wall, commonly called Traitor’s Gate, through which it has been customary, for the greater privacy, to convey traitors and other state prisoners by water, to and from the Tower: the water of the ditch having here a communication with the Thames, by means of a stone bridge on the wharf. However the Lords committed to the Tower for the last rebellion, were publicly admitted at the main entrance. Over this water-gate, is a regular building terminated at each end by a round tower, on which are embrasures for cannon, but at present none are mounted there. In this building are an infirmary, a mill, and the water-works that supply the Tower with water.