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DUB
The only dairies are those for the supply of Dublin with
milk and butter, which, however, are of great extent and
number. The principal manures are lime and limestone
gravel, of which the latter is a species of limestone and
marl mixed, of a very fertilising quality, and found in
inexhaustible quantities. Strong blue and brown marl
are found in different parts, and there are likewise beds
of white marl; the blue kind is preferred as producing
a more durable effect: manures from Dublin, coal ashes,
and shelly sand found on the coast, are also used. The
implements of husbandry are of the common kind, ex-
cept on the farms of noblemen and gentlemen of fortune.
The breed of cattle has been much improved by the
introduction of the most valuable English breeds, which
have nearly superseded the native stock. The county
is not well wooded with the exception of plantations
in the Phoenix Park and the private grounds of the
gentry: there are various nurseries for the supply of
plants. The waste lands occupy 10,912 statute acres:
the largest tract is that of the mountains on the south-
ern confines, extending about fifteen miles in length and
several in breadth. The scarcity of fuel, which would
otherwise press severely on the industrious classes,
from the want of turf nearer home, which can be had
only from the mountains in the south and the distant
commons of Balrothery and Garristown on the north,
is greatly diminished by the ample supplies brought by
both canals and by the importation of English coal.
The county presents several interesting features
in its geological relations. Its southern part from
Blackrock, Kingstown, and Dalkey forms the northern
extremity of the great granitic range which extends
through Wicklow and part of Carlow. The granite
tract is bordered by a range of incumbent mica slate,
which extends eastwards from Shankill and the Scalp
to the hills of Killiney, and on the western side com-
mences near Rathfarnham, passes to the south of Mont-
pelier hill, and occupies the upper part of the hollow
which separates Seefinane mountain, on the east, from
Seechon on the west: in this hollow are displayed some
curious intermixtures of the strata of mica slate, granite,
and quartz. In the descent from Seechon mountain, both
south-westward and north-westward, towards Rathcool,
the mica slate passes into clay slate, containing fre-
quent beds of greenstone, greenstone slate, and green-
stone porphyry, and occasionally likewise of quartz.
The Tallaght hills consist of clay slate, greenstone,
and greenstone porphyry, interstratified; the latter rocks
more particularly abounding in the eastern quarter.
Rathcoole hills,and the range extending from them south-
westward, are composed of clay slate, clay slate conglo-
merate, and grauwacke slate, alternating with each
other. The low group west of Rathcoole is composed of
clay slate, grauwacke, grauwacke slate, and granite, of
which the last is found remarkably disposed in subor-
dinate beds in the prevailing grauwacke slate of Wind-
mill hill, whence some of them may be traced westward
to near Rusty hill. This county contains the only strata
of transition rocks known to exist in the eastern part of
Ireland. They appear in detached portions along the
coast from Portrane Head, by Loughshinny, Skerries,
and Balbriggan to the Delvan stream, the northern limit
of the county. The rest of the county, comprising
nearly the whole of its plain surface, is based on floetz
limestone, commonly of a blueish grey colour, often
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DUB
tinged with black, which colour in some places entirely
prevails, especially where the limestone is interstratified
with slate clay, calp, or swinestone, or where it abounds
in lydian stone. The black limestone in the latter case
is a hard compact rock, often of a silicious nature,
requiring much fuel for its conversion into lime. Calp,
or “black quarry stone,” which is generally of a black-
ish grey colour and dull fracture, and may be consi-
dered as an intimate mixture of limestone and slate
clay, forms the common building stone of Dublin; it is
quarried to a great extent at Crumlin and Rathgar.
Besides carbonate of lime, it includes considerable quan-
tities of silex and alumen, traces of the oxydes of iron
and manganese, and a small proportion of carbon,
which gives to it its dark colour: by exposure to the air
it undergoes a gradual decomposition. The elevated
peninsula of Howth consists of irregular alternations of
clay slate and quartz rock, both pure and intermixed,
on its southern coast the strata present some extraor-
dinary contortions. The only metallic ore at present
found in considerable quantity is lead, once abundantly
raised near the commons of Kilmainham, and at Killi-
ney; a much more productive vein on Shankill is now
being worked by the Mining Company of Ireland. White
lead is found in small quantities; the ore is smelted and
refined at Ballycorus, in the immediate vicinity of the
mine: on Shankill is a tower for the manufacture of shot.
At Loughshinny is a copper mine, and at Clontarf a lead
mine, both now abandoned. On the south-western side
of Howth, grey ore of manganese and brown iron-stone
have been obtained in considerable quantities; and a
variety of earthy black cobalt ore has been found there.
Coal is supposed to exist near the northern side of the
county, and unsuccessful trials have been made for it
near Lucan. Among the smaller minerals may be enu-
merated schorl or tourmaline and garnet, frequently
found in the granite; beryl, a variety of emerald, which
occurs in several places; and spodumene, which is in
great request from its containing eight per cent, of a
newly discovered alkali, called lithia, is procured at Kil-
liney, as is also a mineral closely resembling spodumene,
designated killinite by Dr. Taylor, its discoverer, from its
locality. The limestone strata usually abound with pe-
trifactions, specimens of which, remarkable for their
perfection and variety, may be obtained at St. Dou-
lough’s, and at Feltrim, about seven miles north-east of
Dublin. The shores of the county, particularly from
Loughlinstown to Bray, abound with pebbles of all
colours, often beautifully variegated, which bear a polish,
and are applied to a variety of ornamental uses”
The manufactures are various, but of inferior im-
portance. The most extensive is that of woollen cloth,
carried on chiefly in the liberties and vicinity of Dublin,
The manufacture of paper is carried on in different parts,
more particularly at Rockbrook and Templeoge. There
are also cotton-works, bleach and dye-works, and iron-
works, besides minor establishments, all noticed in their
respective localities. The banks of the numerous small
streams by which the county is watered present divers
advantageous sites for the erection of manufactories of
every kind within a convenient distance of the metropolis.
The great extent of sea-coast affords facilities for obtain-
ing an abundant supply of fish. Nearly 90 wherries,
of which the greater number belong to Skerries and
Rush, and the others to Howth, Baldoyle, Malahide,