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Haugh of Drimmie Bridge
River Ericht, near Blairgowrie, Perth and Kinross, Scotland, UK
associated engineer
John Justice Snr
John Justice Jr
date  circa 1823
era  Georgian  |  category  Bridge  |  reference  NO169502
A delicate yet strong wrought iron multi-stayed suspension bridge designed by John Justice, father or son. It is one of only five known Justice bridges, and possibly the earliest. Its design represents a significant change in early iron bridge construction, from arched bridges to flat spans. The bridge remains in use and has Category A listing.
It is not clear whether Haugh of Drimmie Bridge was designed by John Justice senior or his son John Justice junior. Both men were part of Justice & Co. blacksmiths in Dundee, which is known to have built five similar lightweight iron stayed bridges in north east Scotland. The most famous is the 1834 Crathie Suspension Bridge on the royal estate at Balmoral, Aberdeenshire. The other three are located in Angus — the 1824 Kirkton of Glenisla Bridge (NO212603), the derelict Loups Bridge (NO594717) near Edzell and the Clova Kirk Bridge (demolished, date unknown) at Glen Clova.
Haugh of Drimmie Bridge over the River Ericht was built for Colonel William Chalmers (1787-1860) of Glenericht House (NO170504) to give access to his estate from the south west. Previously thought to have been constructed around 1830, it is described as "erected by him [John Justice] in 1823, for Colonel Chalmers, at Glenericht" in Robert Monteath's Miscellaneous reports on woods and plantations (published 1827).
The bridge spans 32m between stone abutments. Its 3.2m wide timber deck is supported by a visually complex wrought iron superstructure hung from two wrought iron pylon-masts embedded in each abutment. The 76mm square masts stand at each corner of the bridge deck and are spaced 4.3m apart, rising 3.1m above the masonry.
The structure is often called a suspension bridge, though its design is closer to a modern cable-stayed type bridge. Seven diagonal suspension stays, 25mm in diameter, extend from each mast to a longitudinal bar below the edge of the deck, with three diagonal back stays, 38mm square, anchored in the ground. The harp arrangement gives a total of 28 suspension stays and 12 back stays. Two stabilisers (intermediate upright rods) link each array of stays, providing additional stiffness. Suspension rod lengths are connected by shackles and cotter pins.
The upper halves of the mast heads are pierced by intricate connections — suspension stays bolted through in line with the bridge, and anchor stays bolted transversely to the bifurcated ends of the stays. The mast bases are supported by double scrolls of ironwork in 38mm square bar. The tops of their heads bend outwards slightly and are clamped to 41mm square section overthrows with an arch rise of 610mm.
The longitudinal edge bars, 76mm deep and 11mm wide, are connected by transverse bow trusses under the deck. The truss ribs are 51mm deep and 10mm wide, the top rib is an angle bar with arch uppermost and the lower rib is a rectangular bar. A short vertical strut connects the ribs at the midpoint of the truss.
Two longitudinal tension rods provide bracing below the trusses. The rods are hung from 35mm by 32mm struts at the quarter points of the trusses, 1.1m apart. Single rods are used over most of the bridge span, though double rods are used for the end 600mm next to the abutments.
Parapet uprights 32mm by 35mm rise from each enlarged eye connection between the suspension stays and the longitudinal side bars, and are linked by five rows of horizontal rails. The parapets lean outwards, 75mm off vertical at the top. The railings terminate at each end at straining posts with single back anchors.
The timber bridge deck is cradled in this web of iron, running between the parapets and over the trusses. Its central carriageway is 2.2m wide with a raised footpath about 500mm wide on either side. The kerbs are 150mm high, intended originally to help horse-drawn carriages stay on track. The deck consists of longitudinal planks 210mm wide and 83mm deep, topped by thinner diagonal boarding.
According to Monteath, the bridge performed well in load tests and "is capable of bearing any weight that can be put on it; indeed, the first trial was seven loaded carts, each drawn by one horse, so as they could be all on it together". He believed "the expense [of constructing the bridge] was not one third of what a stone bridge would have cost, although plenty of stone is to be found on the spot". Apparently all the ironwork totalled only around 5 tonnes in weight.
In October 1971, Haugh of Drimmie Bridge was listed at Category A as "one of the finest surviving early suspension bridges in Scotland". In September 1976, a series of detailed bridge drawings were prepared, now in the Canmore archive managed by Historic Environment Scotland.
The bridge is located on private land and remains in use by the estate’s traffic. However, a notice warns that only one vehicle at a time may cross the structure, of maximum weight 2 tonnes and at no more than 3mph (4.8kph). The deck was replaced with new timber, laid to the same original pattern, sometime between 2006 and 2012 (exact date unknown).
Contractor: Justce & Co, Dunde
Timber deck replacment (post 2006): Strong Bridges Ltd, Crieff
Research: ECPK
bibliography
"Miscellaneous reports on woods and plantations" by Robert Monteath, James Chalmers, Dundee, 1827
http://happypontist.blogspot.co.uk
http://portal.historic-scotland.gov.uk
https://canmore.org.uk
www.blairgowrieandrattray.org.uk
www.ice.org
www.scotlandsplaces.gov.uk
Location

Haugh of Drimmie Bridge