The Bottle Oven
An essay by Sir George WadeThe bottle ovens which for generations have been such a dominating feature of the Potteries landscape are rapidly vanishing, and soon there will be none at all. This is a very sad reflection for old potters like myself who remember the days when there was no other kind of oven but the majestic bottle type.
All bottle ovens, even when built to the same plan and specification, were different. They all had temperaments and mostly female at that! To get them to produce good ware one had to coax, humour, even to love them! A change of wind, weather, humidity or fuel would upset them thoroughly with consequent loss of ware, due to nothing, so the fireman would assure you, but bloody-mindedness on the oven's part.
A bottle oven would last for a century, but it would keep its character all that time in spite of modifications Some of them were respected, others were feared, and some were absolutely hated and were known by rude names.
|'Placing' or 'setting-in' the glost bottle oven|
Photo: Source unknown Date: 1950s
Now to the operation of a bottle oven. When all the precious saggars had been placed and the clammings built up, fires were started in each mouth with oil soaked rags and odd pieces of wood on which were placed cobbles of coal steadily built up into a fire.
To look into the oven through the spyhole at this stage was a miserable experience; a flickering light from each 'bag' just enabling you to see the wisps of smoke and the condensation running down the bungs of cold saggars. Everything appeared cold, wet and hopeless, but when you looked in a few hours later what a change! A beautiful radiance emanated from every part of the inside. No smoke could be seen, everything was one solid mass of rosy heat. Damn Blastus (the god of Potting) had established himself in his temple and the steady draught which was drawn through the oven sounded like a deep organ note. The trial rings could dimly be seen leaning against one another at an angle, and it required no small dexterity to put in the trial rod, seven or eight feet of half inch round iron, hook out one trial and get the rod out before it started to melt and bend.
With infinite care the baitings were put on leaving a critical space over the top of the coal varying with the requirements of each part of the oven as revealed by the measurement of the trial rings. Dampers and air inlets were all carefully controlled, and steadily the temperature of the tons of saggars and ware rose towards the finishing point. Finally came the ‘soaking’ period when the top temperatures were maintained to get even distribution throughout the oven.
Then the giant oven would be left to cool down after its labours, and anxious people would be eagerly awaiting what would be revealed when it was 'drawn' a day or two later.
Would the ware that was not too 'hard fired' owing to too high a firing temperature be too 'easy fired' having not been fired hard enough, and if it were neither hard nor easy, how much would have 'dunted' that is cracked during cooling? And if it had not been too hard or too easy fired, or dunted how much would be 'reduced' to a blue colour by too much smoke? And out of any ware which had not been easy or hard or dunted or reduced, how much would be 'flashed' by too quick firing? And out of that ware which had safely survived easy firing, hard firing or dunting or reduction or ﬂashing, how much would have brown spots on?
Those were only a few things on ones mind until a biscuit oven was emptied, but what about a 'glost'
oven? To all the above hazards add for glazed ware: Would it survive the crazing test? Would the colours be smeared by sulphur? Would the cobalt colours ‘strike' their innocent neighbours by volatilizing a blue tinge on to them? Would the glazes run down and stick? Would they be 'smoked'?
Who would be a potter!?
The above puts me in mind of the new Natural Law which the late Dr Mellor discovered as a result of his studies of the Pottery Industry. He called it THE LAW OF THE INNATE CUSSEDNESS OF INANIMATE OBJECTS which operates like this:
If there is a single blemish on an important piece of pottery it is always in the most prominent part, if you over fire part of an oven and spoil the ware, it is always a most overdue order for your most important customer who has already been let down three times, and so on and so on.
Slight manifestations of Mellor's Law have been noticed in other industries, but the sublime examples of it come from the old bottle ovens which were truly selective in their misdeeds.
Soon all the bottle ovens will be gone and with them will vanish men I much admire - the Placers and the Firemen.
The Placers had to be men of superb physique who could carry a saggar weighing 60 to 70 lb up a high 'horse' and place it with unerring precision on top of a bung of saggars so that it was vertically and horizontally true. They worked like beavers under dismal conditions and considerable risk, and had a team spirit and sense of responsibility which was admirable in the extreme.
The Firemen were the Arch Druids of the factory, their word was law. Theirs was the responsibility of submitting the whole output to the test of the ﬂames, They could make or mar a business, they could ruin or keep in work hundreds of people.
They were patient, knowledgeable, reliable and firm. Woe betide the boss who wanted to alter the firing cycle to save a little coal. "No sir, if we shorten the time we shall get smoked ware. All right sir, if you say so, I must, but don't say I didn't warn you.
Out would come smoked ware alright and the fireman's reputation would be enhanced. Of course the boss being in bed at 3am had not seen him close off all the dampers for a longer period than usual. Yes they had their ways, but as a class they were unbeatable for trustworthiness, reliability and skill.
Sir George Wade
For definitions of unusual Potteries words go to The Potbank Dictionary here>