Tony and Alan,
Thanks for your interesting contributions. Exactly the sort of info I
was hoping for.
I still don't see why, on geological timescales, the salt has not
dissolved, there is movement of water through every rock, whether it is
porous like sandstone, or simply full of fractures. Nor do I see how
such a mine, however well instrumented, can be anything like immune to
disaster. However, this is not an engineering list, so I will leave this
subject, and pose another question which is relevant to this list:
How does the total quantity of salt obtained from mining compare to that
produced by boiling sea water in salt pans? And was some of the mined
salt dissolved and boiled to purify it?
The reason for the question is that I am very interested in early coal
mining in Central Scotland, where I come from, and know that on the
Forth estuary, almost as far upstream as Clackmannan, where the salinity
is questionable, a great deal of small coal was used in the seemingly
inefficient salt pans. I wondered if it would have been more sensible
to have imported the salt, presumably by sea, from Cheshire, or abroad.
Obviously the salt pans were where the coal was accessible, pre-dating
the Clackmannan and Alloa wagonways for example, but it might have made
sense to take the coal downstream by boat to areas of greater salinity.
It looks as if the coal must have been taken overland at least a mile
to Kennetpans (NS913889), because the mine workings closer than that
date from after the salt panning era.The Old Statistical Account does
of course mention all this, but is invariably short on geographic
detail. My late father found that the houses at NS928882 were built upon
ash from a series of salt pans, this being in Kincardine village, so the
overall coal consumption must have been large. Again, the nearest mine
of the correct age was at least a mile away, later workings were within
half a mile.
It just seems to me to be such a waste, in the 17th century they were
using the coal, with great difficulty, simply for making salt, very
little apparently being used for domestic heating purposes. I wonder
why they bothered, there was plenty of coal down-river where the
salinty was greater,and the salt, being much less massive than the coal,
could easily have been transported up-river. In fact, a few miles
downstream, coal was accessible by adit, above sea level, but near the
shore, so why do it the hard way in the wrong place, with shafts
in waterlogged ground a mile inland? Or have I overlooked some basic
factor such as politics, or land ownership?
Alan Campbell
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