AT HANGMAN'S WOOD, GRAYS.
235
to a height of perhaps 15 ft. above the roof of the chambers. We were
surprised to find many rope-marks in the chalk of the shaft, close to
the roof, just where they are common in the open shafts, and looking
just as fresh and recent. The hole, some 2 ft. square, connecting the
longest chamber of No. 11 with one belonging to No. 7, was cut on
resuming our work this year. It was made partly to allow of a current
of air through No. 11, in which we proposed to sift, partly to test
the accuracy of the ground plan, which had been made in 1884, and
which showed the two chambers in close proximity. As No. 7 was
the first pit entered from No. 3, and No. 11 the last, the accumula-
tion of small errors might easily have produced a considerable dis-
crepancy between the plan and the real state of things. Fortunately,
our test showed the substantial accuracy of the ground plan.
The chalk at Hangman's Wood appears to be lying nearly flat, a
well-marked band of black flint being conspicuous from 5 ft. to 8 ft.
above the floor in those pits not too much filled up to show it. The
usual height of the chambers appears to be from 16 to 18 ft. ; in
No. 5 they were found to be from 21 to 22 ft. The thickness of the
chalk roof varies from about 6 ft. to less than 2 ft ; perhaps the
average is about 3 ft. The floor of adjacent pits seems to vary in
depth from the surface from 2 to 3 ft., the total depth varying from
78 ft. to 81 ft., or thereabouts. Putting aside the long slope which
often occupies a considerable area towards the distal end of a
chamber, the floor has always been found to be quite smooth and
nearly horizontal.
We have found the marks of metal picks to be equally common
in the open and closed pits, their abundance and even distribution
showing that these deneholes certainly owe their present forms and,
in all probability, their origin to users of metal tools. In most of
the pits, especially towards the roof, the pick-marks look very fresh.
Around many are still sticking small patches of moist chalk which,
clinging to the picks, had been cast off as the blows were delivered,
and had thus bespattered the walls of the chambers.
The first mound examined was that at the base of No. 3.4 Being
anxious to note carefully the nature of the section it presented, we
with the assistance of Mr. H. A. Cole, ourselves cut a trench across
the mound to the entrances of the two lateral chambers farthest from
4 For plan and section of this pit see Trans. Essex Field Club, vol. iii., plate ii.