"You say these fortifications lie in the region of Torres Vedras.

Can you be more precise ?" "I think so.

But again I warn you that I can tell you only what I infer.
I judge they will run from the sea, somewhere near the mouth of the Zizandre, in a semicircle to the Tagus, somewhere to the south of Santarem.

I know that they do not reach as far north as San, because the roads there are open, whereas all roads to the south, where I am assuming that the fortifications lie, are closed and closely guarded." "Why do you suggest a semicircle ?" "Because that is the formation of the hills, and presumably the line of heights would be followed." "Yes," the major approved slowly.

"And the distance, then, would be some thirty or forty miles ?" "Fully." The major's face relaxed its gravity.