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Despite Railtrack's best efforts in recent years, the Tay Bridge disaster remains one of Britains worst ever railway accident. A terrific storm, which had spread mayhem and destruction throughout central Scotland, was howling down the Tay just as the Edinburgh train was crossing the bridge. As the train reached the "high girders" at the centre of the bridge, they suddenly collapsed - plunging the train and its sevnty-five passengers and crew into the icy waters. There were no survivors, and only forty-six bodies were ever recovered.
 The bridge, which had been hailed as an engineering masterpiece on its opening the previous year, was found to have been severely flawed. The official enquiry discovered that the iron superstructure was of inferior quality and had been badly maintained. Most damning of all, little or no account was made of wind pressure in the design of the bridge. The enquiry laid the blame at the door of the designer, Sir Thomas Bouch. Bouch vehemently denied the charge, but his career was in ruins. He died just ten months after the fall of the great bridge.

Though none of the passengers were saved, there was a survivor of a sort. The engine that had hauled the train to its doom was recovered from the river bed and put back into service. Sardonically nicknamed "The Diver" by railway staff, it carried on working for the North British Railway until 1908. (typical of a scot eh?)

The first Tay rail bridge was completed in February 1878 to the design of Thomas Bouch. Bouch was responsible for the design, construction and maintenance of the bridge. Most of his bridges were lattice girders supported on slender cast iron columns braced with wrought iron struts and ties. The building of the Tay bridge culminated in him being knighted. The Tay bridge was nearly two miles long, consisting of 85 spans and at the time was the longest bridge in the world. The spans carried a single rail track; 72 of these spans were supported on deck spans, the remaining 13 navigation spans were through girders. These "high girders", as they were known, were 27 ft high with an 88 ft clearance above the high water mark. It was these spans which fell. Most of the deck spans, all of which remained standing, were transferred to the present Tay rail bridge. At the time of the collapse Bouch was working on the design of the proposed Forth Bridge. In consequence, the design of the bridge was transferred to Benjamin Baker and Sir John Fowler.

A Court of Inquiry was set up to try and ascertain the reason for the collapse of the bridge. The Court of Inquiry report (8) concluded that, "The fall of the bridge was occasioned by the insufficiency of the cross bracing and its fastenings to sustain the force of the gale." The Court of Inquiry indicated that if the piers, and in particular the wind bracing, had been properly constructed and maintained, the bridge could have withstood the storm that night, albeit with a low factor of safety - 4 to 5 was the norm at the time. Sir Thomas Bouch was held chiefly to blame for the collapse in not making adequate allowance for wind loading. He used a wind pressure of 10 lbsf/sq ft for the design of the Tay bridge. It is interesting to note that when working on the design of a proposed Forth bridge (1866) he used 30lbsf/sq ft(6). To this day, however, there is still speculation as to the fundamental cause and as to whether or not the designer, Thomas Bouch, was to blame.

OKay sorry for the very long post but, i once heard a theory that a contributing factor in the failure was that the iron was so defective, the suppliers had mixed iron filings and album (egg white) and pasted them into the cracks. Has anyone ever heard this theory or got other explanations?


okay thought id post this also, a rather infamous poet (though i use the word loosley) penned this about the disaster, its strange to see someone write about engineering terms rather than the usual flowery stuff.

It must have been an awful sight,
To witness in the dusky moonlight,
While the Storm Fiend did laugh, and angry did bray,
Along the Railway Bridge of the Silv'ry Tay,
Oh! ill-fated Bridge of the Silv'ry Tay,
I must now conclude my lay
By telling the world fearlessly without the least dismay,
That your central girders would not have given way,
At least many sensible men do say,
Had they been supported on each side with buttresses,
At least many sensible men confesses,
For the stronger we our houses do build,
The less chance we have of being killed.


Thanks, etch, for an interesting story.


John Prebble's bopok 'The High Girders' refers to the use of a compound to patch holes in the iron. This was commissioned by the local representative for the company, and was not done with Thomas Bouch's knowledge or authority.

The mixture was made of iron filings and cement, and was known as 'Beaumont's Egg' (hence the rumour that it was made of egg white). I suspect that this name is a corruption of the french 'Beau Montage' - literally 'Beautiful face/covering'.


The Tay Bridge Poem was indeed written by an infamous poet.
William Topaz McGonagall, poet and tragedian of Dundee, has been widely hailed as the writer of the worst poetry in the English language.
A self-educated handloom weaver from Dundee, he discovered his discordant muse in 1877 and embarked upon a 25 year career as a working poet, delighting and appalling audiences across Scotland and beyond.

This site aims to provide a comprehensive guide to the life and works of William McGonagall, including his remarkable (and unintentionally hilarious) autobiography. Please click on one of the headings below to begin your visit.

Poetic Gems
Though he's best known nowadays for The Tay Bridge Disaster, McGonagall actually published well over 200 poems in his lifetime. Explore this selection of his best(?) work, or try the "pick of the day" below...


There has been some interesting research on this suject by Dr. Peter Lewis of the Open University in Milton Keynes.  Dr. Lewis is proposing that the Tay Bridge disaster was caused by uneven section of rail tracks.  Which, in turn, caused the train to "wobble" side to side, similar to the problems with the Millennium Bridge over the Thames.  I can't seem to locate the article right now but it I read it back in January 2003.

Chris Crosby, P.E.


Hi etch

Yes I read the book "The High Girders" in which was mentioned the paste they filled the blow holes in the castings with,"The Beaumont Egg" as previously mentioned.
It is perphaps also worth mentioning a couple of other points if my memory serves me correctly:-

       1. The wind allowance of 10lbsf/ft^2 was
          actually reccomended to Bouch by the astronomer
          Royal but this fact was never brought out at the

       2. Also Bouch employed a mathmatician who's name I
          cannot find at present, but he performed some
          calculations and checked some of Bouch's
          calculations, interestingly this same mathmatician
          was employed by Baker and Fowler on the Forth

I find the latter quite astonishing considering that poor Bouch was ruined following the pulic inquiry.




The material used to patch castings is called “Foundry Man's Putty”.  I’ve seen references to recipes in old handbooks.  In addition to the afore mentioned ingredients there was dash of graphite.  

PS: It is still used.


I read somewhere that parts of the old Tay bridge were used in the construction of the new one.

Very reassuring, though it's stood up for over a century.

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