Ah, the blast furnace. A reliable feature of every GCSE in science. I imagine it like a blender. Into the top he threw in (or charged) his vital ingredients: coke, iron ore and limestone.
He then turned on the power - heating and agitating (thanks to water powered billows at the bottom - they were on the right in this picture),
until the iron ore lost its oxygen to the carbon in the coke, and the molten metal (which conveniently separated from the rest at the bottom) could be drained out just here.
Coke had two main advantages: it contained much less sulphur (which meant the resulting iron was purer and better quality), and there was a lot of it around which meant Abraham Derby could go in for mass production. Since iron is so incredibly useful for making reliable and uniform parts of machinery, the use of coke in the blast furnace initiated the industrial revolution.
I do like these old industrial sites with their heat-singed bricks, and mysterious pipe-work,
and walls with outlines of previous buildings like scribbles on a palimpsest.
Who worked here?
Who made this pipe?
And who drew curtains over this window?
Maybe William Ball once strode here (though I doubt it). He was an iron-worker (a 'puddle-worker') and was celebrated because he weighed (what was then, but I suspect no longer) an extraordinary 40 stone (560 lbs, 254 kg), and in 1850 had to be lifted onto an unfortunate horse to lead a procession. Here is his chair (which doesn't seem that large) and picture. He is wearing coloured glasses because his eye was injured by molten metal.
They are preserved in the iron Museum (below in the distance on the right).
In subsequent years the British nation went a bit mad over iron and in the museum there were plenty of examples:
railings and chairs,
pots, trestle-legs and grates,
intricately-latticed stove covers,
and the famous ironbridge just down the road.
Cast iron is still the essential main component of the Aga and Rayburn stoves which are made on the adjacent site.
It is a pretty area - with brick built houses tumbling down the slopes
to the river Severn (essential then for the transport of the iron, ore, coke and limestone).
The industry prospered and declined, prospered again and then eventually lost out to other areas which were more centrally and favourably placed. The scientific and literary institute built by the Darby family has now become an attractive youth hostel
and the 'industry' (apart from the Aga factory) now mainly tourism.
This allows the poppies to grow
but close by the bed and breakfasts, ice-cream shops and pubs of the Ironbridge centre there are run-down garages and vacant plots. It is a typical sight in today's Britain. Tourism is a precarious activity to rely upon, and although manufacturing iron was no doubt dangerous, dirty and hard, at least it was tangible, creative and a useful source of wealth. I have long wondered how a nation like ours can survive by producing nothing but services. Perhaps we need to bring back a little of the spirit of Abraham Darby.
There is more information about the place on the Ironbridge's excellent website.