The bridge after the collapse |
The
Tay Bridge Disaster of 1879 is well known to the people of Tayside and Fife . Children in primary schools learn about it; over
the years there have been various articles about it in the local press; several
books have been written about it; and on the 134th anniversary of
the Disaster, on the 28th
December 2013 , substantial granite memorials were erected to the
victims at moving ceremonies on both sides of the Tay . One might be forgiven for imagining that the
last word had been written on the subject, and that there is no more left to
say.
And yet there are two highly important – indeed central – aspects of the story about which there is still a vigorous debate and, as yet, no firm consensus. These are the cause or causes of the collapse, and the true number of the victims lost.
The directors nervously cross the bridge before it opens |
At the time of the disaster, the bridge had been standing for barely eighteen months. The longest bridge in the world at the time of its constructions, it was hailed as an engineering triumph. Famous visitors from all over the world came to marvel at its size and splendour, including the Emperor of Brazil, Prince Leopold of the Belgians, and former President of the United States,Ulysses S. Grant. Even Queen Victoria herself ventured out of her self-imposed seclusion to ride across the bridge and attend a civic reception in Dundee. At the grand opening, the Piper of Dundee played and poems in its honour were read.
In the following year, when the bridge fell, how many perished? It has long been accepted that all
the passengers and crew without exception were killed, as the train plummeted
into the river from a height of nearly 90 feet. What is not so clear is just
how many passengers there were on the train at the time. Most commentaries on
the disaster in recent years have opted for a figure of around 75, and there is
good evidence for this number. For one thing it was the figure accepted by the
Court of Inquiry set up immediately after the collapse. The Court in its turn
based its conclusion on the evidence of station staff at St Fort station,
where, for whatever reason, it was the normal practice for the tickets for
passengers travelling to Dundee to be
collected. These officials reported that they had collected 56 tickets, to
which should be added passengers with season tickets, those travelling beyond Dundee and the members of the crew – a total of between
72 and 75.
Yet
there was another source of evidence, arguably more robust. All deaths
associated with the bridge were registered with the Parish of St Mary’s in
Dundee, and the death certificates ultimately lodged in the National Archives
of Scotland in Edinburgh .
These certificates number only 59 – exactly the same names and number as were recorded
in the police list in the archives of the police in Dundee .
Of these 59, 47 were male, and 12 female. In the event, only 46 bodies were
ever recovered. Moreover, from time to time the local press published the names
of victims, and the latest of these, on 1st January 1880 , included only 56 names
In
other words, the only incontrovertible evidence for the number of victims
supports the conclusion that there were 59, rather than 75. Of course it is
still possible that there were more, who in one way or another escaped
scrutiny, but it seems highly improbable. The great majority of the known
passengers were local – typically travelling back to their work in Dundee after
visiting families in Fife . It is a reasonable
assumption that the same would have been true of any other passengers not
recorded in the list of death certificates. Could it be that some 16 people
were also lost without family, friends, or employers ever noticing? While there
may have been more than 59 victims, if there were, we do not know their names or how many there were. This is
why the Memorials raised to the victims in 2013 firmly state that ’fifty-nine
victims, men women and children, are
known to have died’ in the catastrophe.
Memorials on the Fife bank of the Tay |
Then, what about the other key question – the
cause or causes of the collapse?
To understand that we need to know something
of the history of the bridge and its construction. The rail bridge over the Tay
was the first stage of an ambitious plan on the part of the North British
Railway company to out do their great rival, the Caledonian, by replacing
passenger ferries across the Forth and Tay rivers with two great bridges, able
to carry rail traffic without interruption between Edinburgh
and Aberdeen .
The Company engaged Thomas Bouch, an experienced railway engineer, to carry this out. Bouch’s original intention was to carry the railway line on a single
line bridge supported for almost all of its length on tall brick columns.
Unfortunately it became only too clear in the course of construction that the
river bed, believed to be solid rock for most of its width, was only partly so
– much of it was in fact composed of conglomerate under a thick layer of mud.
This
realisation caused a rapid rethink, and Bouch came up with an alternative to
support the remainder of the bridge with towers made from cast iron columns
bound together with wrought iron tie bars. These tie bars in turn were attached
to the columns by nuts and bolts which passed through holes in lugs, cast
integral with the columns. It is generally accepted that it was these cast iron
lugs which fractured, rendering the towers unstable, and initiating a
progressive collapse of the structure, taking with it the train.
Joints with Lugs |
It is
here that the consensus breaks down. Broadly there are two schools of thought
about the causes of the collapse – either the train brought down the bridge, or
the bridge brought down the train.
In the
first of these two camps we find Bouch himself. He was firmly of the opinion
that what had brought down the train was the accident of a second class
carriage coming off the rails, catching on one of the side girders, and ripping
the whole structure apart. Some colour was given to this explanation by the
fact that there was a known distortion at one point in the rails, caused it has
been claimed by an accident in the course of construction when two of the ‘high
girders’ were blown off their supports into the river. One of these was
repaired and reused, leading to a ‘kink in the rail’ which could have unsettled
a carriage as it passed over it. Bouch pointed to certain scrape marks on one
of the side girders, which could have been made by contact with a carriage.
Against
that there was the fact that the marks were too high up to be reached by a
toppling carriage. Dugald Drummond, chief engineer for the North British, for
his part was convinced from the state of the rolling stock, that all its
components had remained on the track as it fell.
A
recent and intriguing contribution to the debate has been the claim that the
lugs failed due to metal fatigue, induced by the passage of trains over the
bridge since its inception. But this explanation has not found favour with
experts in the field, who have concluded that the operational life of the
bridge was far too short for metal fatigue to have set in.
So what
are we left with? If the bridge itself was the cause of the demise of the
train, how did that come about?
Here we
need to return to the conclusions of the Court of Inquiry, which amongst other
things focused on the design of the bridge, with particular reference to the
question of wind pressure, and the design of the lugs, crucial to the failure
of the whole construction. Bouch came in for particular criticism for his
failure to make sufficient allowance for the pressure of wind against the
fabric of the bridge, although it was clear that even officials at the Board of
Trade, including the Inspector of the bridge, Major General Hutchinson, were
not accustomed to make any such allowance for lattice girders of the length and
type involved. Nevertheless it is the firm opinion of modern experts that one
of the key causes of the collapse was the extreme pressure of wind on the
fateful night.
The
second major factor was the design and method of manufacture of the lugs to
which the tie bars had been bolted. The most obvious problem was that, in the
process of casting, the holes in the lugs, which were to take the connecting
bolts, ended up being conical in shape instead of truly cylindrical. This had
the effect of concentrating all the stress of the connection on a narrow ring
of metal. On top of that, as a cost cutting measure, Bouch had specified bolts
which were one eighth of an inch smaller that they should have been.
Belah Viaduct |
Again, if
only Bouch had chosen to use the kind of wrought iron ring clamps he had used on the
Belah Viaduct in the North of England, instead of the fragile lugs, the
disaster might well never have happened at all. Why didn’t he? Because they
were too expensive.
Various
other contributory factors have been cited as explanations of the fall. The
great height of the bridge above the high water level, which arguably made it
less stable, was due to fears of the authorities in Perth , up river from the bridge, that their
seaward trade might be affected. That it was a narrow single line bridge at all
was down to the directors of the North British – again a matter of cost. That Henry
Noble, charged with the maintenance of the bridge after it came into operation,
had tried to cure ‘chattering’ in the bridge components as economically as
possible by hammering wedges of iron into them, may well have forced the bridge
out of true.
Belah Wrought Iron Clamps |
But in
the end one comes down to the simple facts.
The bridge collapsed in a fierce and unremitting gale for two
fundamental reasons – the lack of a sufficient allowance for wind pressure in
the design, and the fatal decision to rely on the cast iron lugs to hold the
towers together, instead of the Belah clamps. Not surprisingly, Bouch, as the
designer of the bridge, was devastated by the collapse of the bridge, the tragic loss of life, and the
ruin of his professional reputation. He survived the fall of the bridge by less
than a year.
The Tay
Bridge Disaster was an engineering catastrophe, but above all it was a human
tragedy. Most of the victims were young, 10 of them 18 or under, the youngest
only 5. But consider the remarkable escape of six year old William Brown. William
lived in Dundee with his widowed mother, one
brother and two sisters. In late December, 1879, he was looking forward to
travelling to Leuchars in Fife with his
grandmother and his elder sister to visit his uncle Charles. But he had been
very naughty – the exact nature of his crime is not revealed – he was given a
severe beating by his mother, and forbidden to go on the visit. That was the
last he saw of sister Elisabeth and their grandmother.
Memorials on the Dundee bank of the Tay. The new bridge in the background. |
Published 20 October 2016, the new and updated edition The Fall of the Tay Bridge, by David Swinfen:
Ann Swinfen
http://www.annswinfen.com
Wasn't there a novel by A J Cronin in which the disaster featured very prominently? It's a very long time since I read it, but it made a powerful impression.
ReplyDeleteWell done for not mentioning McGonagle!
ReplyDeleteFascinating post: thank you.
Knowledge of the disaster always lends a certain frisson to crossing the modern Forth and Tay bridges, despite all the years they've stood.
Fascinating piece of clear detective work. thank you!
ReplyDeleteReally interesting, thank you. I recently made my American husband read the McGonagall poem - he was in recovery for quite a while after that!
ReplyDelete