BIRDS OF THE THAMES VALLEY (ESSEX ONLY). 155
place around Dagenham Gulf, and only a limited portion is now
accessible, a large portion of the adjacent ground having been
enclosed with a view to the erection of a motor factory. From
the Breach to Rainham the river bank is a mountain of smoulder-
ing and stenching rubbish, the ghoulishness of which would be
difficult to surpass. The next stretch, from Rainham, is occupied
by the Government ranges and is inaccessible. The part between
Purfleet and Grays is accessible, but, although it includes Stone-
ness, of which Mr. Horn has made the most, it is hardly
worthy of the naturalist's attention as it has been so much
commercialised. Starting from Purfleet, one meets a series of
obstacles in the form of staircases, which impede one's progress
along the wall as the gendarmes do on an Alpine arete. Their
purpose is to bridge a series of jetties, thrown out across the
sea-wall by two oil companies and a cement works, but after
these are passed there are about two miles of river free from ob-
stacles. Most of the bank from Grays to West Tilbury is
occupied by factories, etc. The stretch from West to East Tilbury
is, or rather was, of considerable interest. I use the past tense as
big changes have taken place recently. In the last few years
this pleasant part of the Thames has been destroyed by the
appearance of another appalling rubbish-heap, and a large portion
of the adjoining marsh is being walled in so that mud from the
river may be pumped into the basin thus formed, with the purpose
of growing sugar beet. The approach to this portion of the river
at West Tilbury has now been closed, but it is still open from Low
Street. Attention to the tract between East Tilbury and
Stanford-le-Hope Marsh, although there are the remains of an old
rubbish dump, will not go unrewarded, as it includes Mucking
Flats, a favoured haunt of the birds. The next stretch, which
finishes at Thames Haven, is occupied by oil tanks. The sea-wall
is built of concrete, and at its eastern end the trespasser finds his
way barred by an iron gate, which can only be negotiated at low
tide. Corringham Marsh, behind the oil tanks, is probably the
best piece of marsh along the Thames and, in spite of the inroads
of the oil tanks, is always of interest. Before it was exploited it
must have been a remarkable locality for birds. The western end
of Canvey Island is still unspoiled, but east of the road between
Benfleet and Holehaven the island has been more or less affected
by the many bungalows which have been and are being