Was our Water Tank Older than 1876?

 There is no doubt that our water tower was built during 1876, as was Settle station.  The line itself was opened for freight in 1875.  Only then was it possible to transport by rail to sites along the line to build the stations and associated buildings.  By far the heaviest and bulkiest components required were the massive CAST IRON beams to support the water tanks.  Two of the line's water tanks - ours and the identical one at Hawes Junction (now Garsdale) - were far bigger than all of the others.  Maybe Carlisle Durran Hill was a big one too.

Why so?  Perhaps it was thought that those places would be busier than those elsewhere so bigger supplies of water would be needed.  Maybe so but not that much busier.   Maybe Settle and Hawes Junction had better or more plentiful water supplies locally.   'Better' may seem to be a strange term for water.  Well as far as steam boilers are concerned the quality of water matters greatly.  Neither too acid (as would drain from peat moorlands) nor too hard as might be expected from limestone areas.  Furring of locomotive boilers was a serious and expensive problem.  Costly and huge water softening equipment was installed at key sites across the nation's railways, at locomotives works especially.   At the Midland Railway's Derby works there were several water softening tanks with cast iron panels identical to ours, at ground level without need of beams:

During the months I was working on the outside of the tank I got to know each component panel very well indeed,  A few things puzzled me.

1. The painted letters on the painted panels.  Only five or so panels bore letters, They were L., R.(inverted), E (inverted), Q (right way up but off-centre) and C (or perhaps another Q whose right side had worn off).   If you enlarge the screen shot below from Restoration Man Best Builds you can see them.  They make no sense.  They had been applied to the outsides of already painted panels - perhaps to identify assembled panels on an existing but redundant tanks elsewhere.  They appear random and incomplete:

2. The tops of the top row of panels have empty square holes at 6 inch centres.  An unnecessary complication in the castings.  Had those panels once had another layer on top of them?

Had our tank's cast iron components come from a dismantled tank or tanks elsewhere?  How about the cast iron beams supporting the tank?  Might they too have been re-used from elsewhere?  By 1876 the Midland Railway might have been keen to economise and surplus items like water tanks may have become available from recent vast alterations to their massive railway arrangements in London.  Midland trains used to terminate at King's Cross when St Pancras opened in 1869.

1879 saw a disaster which shook Victorian confidence to its core,   On  Sunday 28 December of that year at night and in appalling weather the high girders of the then recently built (started in 1871) Tay bridge in Scotland collapsed under the weight of a passenger train, killing all on board.   Those girders were made of cast iron - a hitherto reliable and strong building material which was cheap and much used in industrial buildings and bridges especially.   Very soon the drawbacks of cast iron were identified and called into question.  Cast iron is brittle.  It is fine for columns in compression but can fail when in tension.  Cast  iron water tank side panels and the supporting cast iron beams act in tension.  The 1870s marked the end of cast iron for tension applications, especially on the railways.   It was quickly replaced by wrought iron and later steel for tension applications.   Yet our water tank was built with cast iron plates and beams in tension just six years before the Tay bridge collapse.

But hang on.   Beams, though supported at each end, are indeed in tension by their very nature yet in a water tower they form an enormous platform SUPPORTING an evenly spread massive load at four foot centres.  In tension they may be to some extent but by far the bigger part of their mass is in COMPRESSION.  Wrought iron or steel girders would be better of course but for now the cast iron beams would do in this application where lives were not at risk in the highly unlikely event of failure.  The tie bars which criss-crossed the tank side plates most certainly needed to be in wrought iron - and they were.  Even so their anchorages to the side plates were to drilled cast iron lugs, cast as parts of the side plates.  This is now known to be a point of weakness.  Of all the dozens of such anchorages in our tank just one had failed.  The evidence is still there today - a broken cast iron anchorage and a large vertical crack on the associated plate from which it springs:

This fracture, near the north east corner of the top tier of tank plates is of no structural consequence for the empty tank but it could and probably would have been disastrous for a full tank.  Tanks of this very type have failed.  An example was this one at Witney in Oxfordshire in 1904:

Did the (by 1876) cash strapped Midland Railway take a chance and re-use expensive surplus tank components for their horribly expensive new line between Settle and Carlisle?  Perhaps.