On the Phosphoric Strata of the Chalk Formation. 
07 
growth of li()])s, having ])roduced more tlian average crops. An exami- 
nation into the subsoil last winter disclosed a rich vein of the fossil marl 
4 or 5 feet helow tlie surface : thus the mystery was explained. In 
several instances the subjacent beds of marl, which were deeply covered 
u|) by drifted soil, have lately been discovered by the peculiarity noticed 
for many years in the growing of the hops. 
'I he influence of this marl upon corn has been equally conspicuoiis j 
the wheat-crops especially having always exhibited a far more vigor- 
ous growth than usual upon the outcrops. There is a very striking 
illustration of the efl'ect produced by a narrow band of the green marl 
which runs through a field of wheat now growing at the N.E. extremity 
of the parish. The strata here are neaily vertical, and the band is very 
thin, so that its direction across the field may be traced by a rank green 
luxuriant belt of wheat about 6 feet in width. 
Near this field, in a section of a quarry of the firestone rock, may be 
seen a seam of the green marl only a few inches thick, lying in its usual 
position betwixt the hard rock below and the soft mail above ; adjoininj^ 
the pit is a hedgerow of ash underwood, the roots of which, having pene- 
trated vertically in single rootlets through the chalk marl, no sooner 
reached the green seam than they struck off laterally, forming a mat of 
thick fibre — evidently showing that they, as well as wheat and hops, 
luxuriated in this peculiar marl. An arable field in which the green 
marl is widtly developed near the surface is remarkable for its natural 
fertility, and has only received manure thrice in nearly thirty years — 
viz. bones, rags, and guano. Not the slightest good resulted frum 
the bone manure, although 40 bushels per acre were put on. 
The above examples are selected as affording natural indications of 
fertility inherent in and specially belonging to these soils. 
On the east of the town of Farnhain the strata are much dislocated, 
and the phosphoric green band, wherever it is discernible, is only a few 
inches thick. On the N.W. of the town, below the Castle, it commences 
at the upper part of the Heart Hop-gardens, running in a W.S.W. 
direction through Beaver's Hill and the central part of Dippen Hall 
farm ; it is, however, frequently interrupted in its continuity by valleys 
which have been denuded since its deposition. Its ordinars thickness is 
from 2 to 4 and 5 feet, though occasionally it attains to from 10 to 15 
feet. 
Some parts of this bed are remarkably prolific in organic 
remains ; but in this respect, as has been already observed, there 
is no regularity of distribution. In the process of digging the 
marl at Dippen Hall a large collection of fossils has been 
obtained, but there is nothing worthy of special notice in them, as 
they comprise almost exclusively the genera and species well 
known as characteristic of the chalk formation. 
The sponges however, comprising varieties of every order of 
organization, are the most prominent and characteristic genus — 
beautiful specimens of the syphonia pyriformis, and other alcyon- 
ites, are profusely abundant. For splendid illustrations of these 
and other beautiful zoophytes, plate xv. a, of vol. iv. of the 
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