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Proceedings of the Royal Society 
its site, there is scarcely a yard of its course from Wallsend to 
Bowness where traces of it are not to be found. Where the stone- 
works have disappeared the fosse or earthen ramparts generally 
show themselves. 
The wall is really an important fortification, consisting of 
several parts. There is first the stone wall, with a deep and 
broad fosse on its northern margin ; next, the vallum or earth wall, 
which at varying distances keeps to the south of the stone wall. 
Then between these was a well-made road. Lastly, there was a 
series of stationary camps, castles, and turrets, for the accommoda- 
tion of the soldiery who garrisoned the structure. 
The length of the great wall is said to be seventy-three and 
a-half miles. It is usually about eight feet thick, and in two 
places it now stands nine and a-half feet high. Its original eleva- 
tion was much greater. 
The stations were military cities, mostly attached to the wall. 
The largest of them contain an area of six acres, some of them 
only three. The stations are distant from one another at an 
average of about four miles. Their form is that of a parallelogram 
with the corners rounded. The first thing which the builders of 
the wall did was to build the station, when they felt that they 
could safely undertake the other parts of the fortification, running 
the wall right and left. The masonry of the gateways is pecu- 
liarly massive and strong. In some of them the joints are as 
close as ever, and the courses as true as they were 1700 years ago. 
As far as can be ascertained, every station had a double gateway 
opening northwards, as well as in other directions. The north 
gate of Borcovicus station (House-steads) must have been much 
used, for its threshold is deeply worn by the feet of passengers. 
That the Romans did not give up to the enemy the country on 
the north side of the wall is shown by a circumstance that the 
garrison at the station of Borcovicus had an amphitheatre provided 
for their amusement on the north side of the wall, where the 
ground outside the wall was best suited for its formation. It was 
not unusual with the Romans to provide amusements for the 
soldiery even upon a campaign. 
In crossing from sea to sea, the wall, about the centre of its 
course, comes near an upheaved mass of basalt. For about ten 
