to prevent a hostile fleet approaching the City. In the year 1707 considerable portions of the wall were laid bare in digging for the foundations of some houses near Bishopsgate, which Dr. Woodward carefully examined, and gave a description of the materials and construction in "Remarks upon the Ancient and Present State of London: Occasioned by some Roman urns, etc., discovered near Bishopgate," originally published in the eighth volume of Leland's _Itinerary_, and afterwards separately. He says: "It was compiled alternately of layers of broad flat bricks and of ragstone. The bricks lay in double ranges, and each brick being but one inch and three tenths in thickness, the whole layer, with the mortar interposed, exceeded not three inches. The layers of stone were not quite two feet thick of our measure. To this height (eight feet) the workmanship was after the Roman manner, and these were the remains of the ancient wall. In this it was very observable that the mortar was, as usual in the Roman work, so very firm and hard that the stone itself was easily broke and gave way as that. It was thus far from the foundation nine feet in thickness. The broad thin bricks above mentioned were all of Roman make, and of the sort, as we learn from Pliny, that were in common use among the Romans, being in length one foot and a half of their standard, and in breadth one foot. The old wall having been demolished, was afterwards repaired and carried up of the same thickness to eight or nine feet in height; or, if higher, there was no more of that work now standing. All this was apparently additional, and of a make later than the part underneath it. The outside, towards the suburbs, was faced with a coarse sort of stone, not compiled with care, nor disposed into a regular method; but on the inside there appeared more marks of workmanship and art. There was not one of the broad thin Roman bricks mentioned above in all this part, nor was the mortar near so hard as in that below; but from the description it may be easily collected that this part, when first made and entire, with so various and orderly a disposition of the materials—flint, stone, and bricks—could not but carry a very elegant and handsome aspect. Upon the additional work now described was raised a wall wholly of brick, only that it terminated in battlements topped with copings of stone. It was two feet four inches in thickness, and somewhat above eight feet in height.... This wall was strengthened and embellished with stately towers, which on the south, together with the wall, are long since become a prey to the tide and weather; but the remains of those on the land side, being fifteen in number, are still to be seen: one thereof, about the middle of Houndsditch, is a Roman construction, composed of stone with layers of bricks. It is situated almost opposite the end of Gravel Lane, on the west of Houndsditch, and is still three stories