182 THE ESSEX NATURALIST
In contrast with the 17 boulders plotted along the edge of the Upland
plateau and over the gravel cap of Thrushesbush, only three conglomerate
boulders occur in the area, if we ignore those in the bed of the Cripsey
Brook, viz., Salter's stone at Nazeing Common, the block at the gate of
Harold Park Farm, and a large boulder in the garden of Epping Priory
Farm (Fig. 2). This absence of stray boulders within reasonable distance
of the series is a common feature of the system, and is particularly marked
in the west of the county, where the only conglomerate surface stones found
are those upon the alignment. Kenworthy, who recorded the White Notley
boulder (52/788177) as far back as 1887 (Essex Naturalist 1, 8),
emphasised that this was the only large block known to him in the district,
although he had seen small pieces dug out of gravel-pits.
Other properties of this series relate to their spacing and the nature of
the subsoil on which they stand. There appears to be no regularity in the
intervals between them, although from experience it is deduced that
individual stones were probably within sighting distance of each other.
Such is indeed the case in many sections of the series, e.g., at Epping
Upland, and through the city of St. Albans, Hertfordshire. It is also very
evident that the line of stones follows as nearly as possible the line of the
glacial and river gravels traversing Essex from south-west to north-east,
which explains its many sinuosities. For example, at the crossing of the
Chelmer opposite Broomfield, the track turns sharply north-north-east to
follow a ridge of gravel leading to Great Leighs.
The section of our track which passes through St. Albans in Hertford-
shire is remarkable for the reason that the constituent stones have survived
in an almost complete series right through the heart of a modern urban
area. From east to west the series is as follows:—
No. Site Map ref. Distance Remarks
1 Verulam ...... 134074 0 yards Ruins of Roman Theatre.
2 Yer Ford ...... 139075 400 ,, Standing.
3 19 Wellclose St. 142074 480 ,, Fragments in garden.
4 Moot House ... 143073 440 ,, Now at Museum.
5 27 New Kent Rd. 14S072 200 ,, Garden.
6 51 Lattimore Ed. 149072 5G0 ,, Garden.
7 Cunningham Hill
Farm......... 163066 1,100 ,. Roadside by gate.
8 Cellbarnes Hospi-
tal Garden ... 175060 1,500 ,, —
9 The Block —Tyt-
tenhanger...... 177060 300 ,, Missing. Known 1020.
10 Hillend Farm
Gate ......... 185059 800 ,, Roadside.
11 Colney Church—
roadside ...... 197062 1,300 ,, Missing since road alter-
ations.
In addition to this closely-packed series of stones, the district of St.
Albans contains many other widely-dispersed specimens, but nowhere is
there the semblance of a continuous trail of related boulders.