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Position 56°26.1' N 2°23.1' W
Built 1807-1811
Engineers - John Rennie (chief); Robert Stevenson (resident)
The Light was first exhibited on 1st February 1811
Total cost (including the Signal Tower complex) - £61,331
9s and 2d (£61.331.47p)
The total
workforce is difficult to ascertain, but the number
must be nearer 110 men, made up, roughly, of 60 Artificers,
35 Seamen, and 15 Executives and Heads of Various Departments;
plus the workhorse, Bassey. The horse pulled the Woolwich
Sling Cart containing the stones for the construction of
the lighthouse from the work-yard in Arbroath to the harbour.
The artificers consisted mainly of masons, smiths,
carpenters, wrights, mortar-makers, and labourers.
Shipping: Floating Light, (Pharos) 82 tons; Schooner
(Sir Joseph Banks) 84 tons; Smeaton, 42 tons; Patriot, 46
tons; and two praam boats (Dickie and Fernie) at 15 tons
each (The complement of Seamen and Masters is listed under
The Builders).
NB - 1 ton = 1.016 tonne metric.
Total height from the foundation to top of lightroom
- 115 feet 10 inches (35.30m).
Building material - Sandstone from Mylnefield near
Dundee, and Craigleith, Edinburgh Granite from Rubislaw,
Aberdeen; and Cairngall, near Peterhead Courses 1-26 - granite
outer casing, sandstone inner Courses 27-90 - sandstone
only Mortar mix consisted of lime from Aberthaw, Wales;
pozzolano or tarras (an earthy substance akin to lava) from
Sicily, Italy, and Andernach, Germany, respectively; also
locally obtained sand. Roman Cement was used for the outside
grouting of the building.
The Light-room is constructed mainly of cast-iron
with copper and brass fitments.
Course 1 (Foundation Course) consists of 18 blocks (4 granite and 14 sandstone). The blocks here measure between 6 and 18 inches (15.2 to 45.8cm)
in thickness. This effectively raised the foundation pit to a uniform level in preparation for the First Complete Course. The foundation stone itself (20 cubic feet) is in this course with the date of 1808 inscribed on it.
Course 2 (First Complete Course) has a diameter of 42 feet (12.80m) and is
made up of 123 interlocking blocks, and measured 12 inches (30.48cm)
in thickness. Many blocks on the lower
courses weighed more than a ton
Course 3 (Second Complete Course) is
made up of 136 interlocking stones and measures 18 inches (48.8cm)
in thickness with an overall weight of 152 tons.
Courses 1-26 are solid; on course 27 (consisting
of 38 stones) is the outside entrance to the lighthouse
and commencement of stone staircase - 32 feet 8 inches (9.95m)
above the foundation level and 17 feet (5.18m) above high
water of spring tides.
Courses 27-38 - This part of the building contains
the stone staircase up to the main house (12 courses); the
walls here have a mean thickness of 6 feet (1.83m).
At Course 39 (consisting of 16 stones) the walls
are reduced from 5 feet 9 inches (1.75m) to 3 feet 2 inches
(96.5cm) in thickness. The height of the building is now
45 feet (13.72m).
At Course 85 (the Light-room and Balcony floor) the
height of the tower is 97 feet 9 inches (29.79m); the diameter
of the tower (outer wall to outer wall) is 13 feet 6 inches
(4.11m). The stones of this course (8 in all) are 7½ feet
long (2.28m), and weigh over 1 ton each.
The 90th or Last course of the masonry part of the
building was completed on Monday, 30th July 1810, at an
overall height of 102 feet 6 inches (31.24m)
The blocks of stones are held together by dovetailing
(rather like a 3-dimensional jigsaw puzzle), “by which
the stones may be said to hook laterally into one another,
forming a vertical bond of connection; but it is on the
gravity of the materials that the chief dependence is placed
for the stability of the fabric.”
In all, 2835 stones were used in the construction
of the Lighthouse
The total weight of Masonry, the Lantern and its
Apparatus is 2083.445 tons.
Implements consisted of Railways, Waggons, Triangular
Crane, Moveable Beam Crane, Balance Crane, Sling Cart, Carpenter’s
Jack, Lewis Bat, Moulds, Pumps, Winch-Machines and Oaken
Trenails and Wedges.
The revolving light of the Bell Rock could be seen,
from an elevated position on land, at a distance of 35 miles
(56.3km). It alternated between a white and a red light
completing its cycle every four minutes; and 8 minutes to
do a 360 deg. revolution - see also below.
The Light-room glass panels (48 in all) were arranged
octagonally around the Revolving Reflectors. Each glass
plate measured 13½ inches (34.2cm) by 26¾ inches (67.9cm)
and was ¼ of an inch (6.35mm) thick. On the balcony were
two Alarm Bells to warn shipping in foggy weather.
The 24 Reflectors (25-inch (63.5cm) copper silver-plated
and parabolic) were placed on a rectangular revolving frame.
The two Major Sides had 7 each arranged in 3 rows - from
top to bottom - 2, 3 and 2. The two Minor Sides, 5 each
- 2, 1 and 2. To achieve the red flash of Bell Rock's unique
light sequence, panes of red-coloured glass were placed
in front of each of the reflectors on the minor sides.
The Light, using spermaceti oil, came from Argand-burners
housed within the reflectors.
57½ doz (690) Flambeaux (flaming torches) were used
for night-work on the Rock.
There are Five Apartments within the main building:
• The first and lowest of the apartments is the Provision
Store. It also contains a winch for raising stores from
the railways to the entrance door of the house;
• The second is the Lightroom Store, containing chiefly
7 copper oil cisterns;
• Above that (the third) is the Bedroom accommodating
three Lightkeepers;
• The fourth is the Kitchen and eating quarters;
• Immediately below the Light Room is the Strangers’
Room or Library.
The lighthouse claimed five lives during its construction. ONE on the Rock itself (missing presumed drowned); ONE in the workshop at Arbroath; and THREE died due to separate accidents at sea.
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