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close this bookBoiling Point No. 21 - April 1990 (ITDG - ITDG, 1990, 44 p.)
View the document(introduction...)
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View the documentWhere Expertise Counts ?
View the documentMonitoring & Evaluation of Stove Programmes
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View the documentAn Aspect of Women & Stove Production in Tanzania
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View the documentThe Stove - A Target Orientation Programme
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View the documentRWEPA NEWS
View the documentStove Journal Profiles
View the documentLetter to the Editor
View the documentNews

Where Expertise Counts ?

by Anne Sefu, Coordinator of the Morogoro Fueltwood Stove Project in ,Vorogoro, Tanzania

Our troubles began in March 1988, out of the blue as it were. I remember the month very well (although we had no idea at the time that it would turn out to have such significance for us) because it was during this time that Viv Abbott and Tim Jones (Ceramicist) of ITDG were visiting us - a pure coincidence, no doubt.


We had begun working with the potters in Ruvuma Village in the Uluguru mountains in mid-1985. For over three and a half years the potters had successfully produced and sold some 2,000 ceramic charcoal stoves, known throughout Tanzania as the Morogoro Stoves.

We had estimated that the average life-expectancy of a stove was about six months so we were completely taken aback when, during the space of three days, five indignant customers turned up bearing the remains of their stoves. Our visitors were the first of a long line of stove users, experts and ceramicists to puzzle over the Morogoro mystery of the exploding stoves. What actually happens is that a stove which appears perfectly whole, upon being lit with charcoal for the first time, gives an audible "pop" and a large crack appears in the stove wall before one's eyes. This had very seldom occurred before.

We verified by our own testing that these and the many subsequent complaints we got were indeed justified. We began to test the stoves before putting them on sale, whether at the project workplace or at the market. In our tests, about 60% of the stoves "burst" before the first charge of charcoal had burnt out.

Over the next 18 months we tried out nearly 2000 stoves, looking for any parameters the burst stoves might have in common. During this time we carried out all kinds of investigations: we tried to test the clay used but found that not only did many of the potters use clay from different sources, but each potter used clay from a variety of sources on different occasions. We tried mixing the different clays with a variety of additives which would be accessible to the potters. We scrutinized the firing process which by this time was in a simple brick kiln which the potters and our team had built together.

It was at this stage that we began to encounter a factor which we, the project personnel, had up to then not taken seriously - witchcraft. The stovemakers themselves had been hinting at this as their diagnosis of the problem for sometime. Very often people who had distinguished themselves in one way or another - who had tried to make themselves out to be a cut above the rest of the community were likely victims of witchcraft. It would be no wonder then if our potters were the target of an evil spell or curse. They had been the centre of a lot of attention since they'd joined forces with the project, not to mention making money from the sale of stoves. This, combined with the fact that the group - numbering around twenty had decided not to take in any new members had apparently caused a lot of jealousy amongst other villagers.


At this point we were fortunate enough to have the assistance of an expatriate potter who not only had several years of first-hand experience with traditional Tanzanian pottery but also - by sheer coincidence - with traditional Tanzanian witchcraft. Consequently, while he was straightening out the somewhat collapsed chequer floor of the kiln and clearing out bits of broken pottery and bricks from the ashes beneath, he was as unsurprised as the potters to discover a neatly-tied bundle of feathers, bones and other not-immediately identifiable objects. The women at once triumphantly seized upon this as proof of the long-suspected mischief perpetrated by those jealous of the group's success.

Well, said 1, triumphant in my turn, if "they" really had put an evil spell on the kiln, we had now got rid of it well and truly because this mtaalamu (expert) had dealt effectively With such uchawi before.

To the immense satisfaction of the women, the stoves which came out of the next firing showed a dramatic improvement over previously fired stoves and to prevent further tampering with the kiln we surrounded it with latterite walls. But our triumph was short-lived. In all the subsequent firings the results were as before: even though most of the stoves which came out of the kiln looked and sounded whole, when charcoal was lit in them they exploded as regularly as before the renovation - and exorcism - of the kiln.

By this time we were beginning to get quite worried. We were acutely aware of the lack of technical expertise within the project: the potter who had been helping us had left to meet commitments elsewhere. We were still convinced at this stage that it was a technical problem we were faced with.

In April 1989, over a year since the outbreak}; of the cracking epidemic, we were joined for about three months by a Danish potter who had earlier worked for several years in an area of Tanzania perhaps even more entrenched in superstitions than our own.

During this period more intensive investigations were carried out on the clay, the products of each potter, the possible additives, and the firing temperature. (1) Our potter worked very closely with the village potters and the latter took part in testing their own stoves.

Consequently they saw at least half of the fine-looking stoves they had spent so much time and effort on crack apart before their very eyes. After a couple of months, the new mtaalamu discerned a distinct pattern which pointed to three factors that should reduce the percentage of cracking stoves to an acceptable level: to use clay which most of the potters seemed to have used during the first three years of stove production; to mix grog with this particular clay; and to fire the resulting stoves at a particular temperature.

The last two items did not present serious problems - the women, having by this time fired together with the mtaalamu many times, were competent in controlling the temperature. There was certainly no difficulty in finding sufficient raw material for the grog: there were dozens of cracked, unsaleable - though still usable stoves lying around. But the first requirement - the original stove clay - did present a problem. The potters had not stopped digging in that spot voluntarily; like all the clay deposits in the area, it lies in someone's field. The farmer of this particular field, known by the name of Mapenzi (love), had allowed the group access to the ground for as long as the field was Iying fallow but now he had established a profitable carrot patch on it. We urged the women to offer Mapenzi compensation for the loss of cultivateable land in exchange for the clay.

To our great relief, at our next meeting with the potters they informed us that they had made an offer to Mapenzi and he had accepted it.

"Great, “ we said, "When can you start? Tomorrow?" There was an awkward pause. Some shuffling about and furtive exchange of glances.

"Well, you see", spoke up the eldest women, "before we can start we have to get our mtaalamu to go and look at the clay. To make sure that it's going to Joe al right. "

This was a little surprising since our mtaalamu had taken a sizeable sample of the clay and tested it in various ways before reaching the decision to recommend it for further trials. But if the potters wanted to be even more thorough, we were willing to go along with that.

"Sure, " said our potter, "can we go and look at it right now?"

Again, istinctly embarrassed pause followed. A couple of the young girls laughed nervously. The potters all obviously felt uncomfortable.

The leader spoke up again:

"Uuh.. actually, I didn't mean this mtualamu. meant our local mtualamu.''

"I see, " said l, "Of course. How soon do you think this could be arranged? You know we need to do these trials as soon as possible, before our mtualamu has to go back home. " "Oh, as soon as we can get enough money together. Everybody will make one stove each from the old clay and then contribute the money they make from it for the fee. Each of us hat to give a hundred shillings."

The agreement we reached was that the project would loan the potters the fees to pay the local expert and the stovemakers would repay us "soon". If our fenders can support a consultancy visit from Denmark to try to solve the problem, they could do the same for a consultant from the very same village at much less cost and, furthermore, payable in local currency.

The spokeswoman tucked the money into the bosom of her dress and undertook to make the necessary arrangements. No doubt the women were convinced that once it was generally known which clay they would be using in future, their disgruntled neighbours would call in their expert to "fix" the clay. Suddenly, the potters' former infuriating and incomprehensible inconsistency over their sources of clay made sense. They had been obliged to change their source from day to day in order to prevent it being bewitched. Now that we were insisting on them sticking to the one clay pit, the potters had no choice but to take preventive measures.

A few days later we heard from one of the potters that the Mapenzi clay had been sanctioned for use. The appointed witch doctor - Mganga - had reportedly visited the site and after performing the necessary rites had slept the night on the clay itself In due course, thirty stoves of the Mapenzi clay-plus-grog mixture were produced, enough to fill the kiln and carry out a trial firing at the recommended temperature, under the supervision of the ceramic mtaalamu.

The result was devastating. The number of stoves that exploded during testing was higher than ever before.

What had gone wrong? Were the results of the previous tests totally misleading? Was the data much of it provided by the stovemakers themselves - on which the tests were based unreliable? Was the preventive medicine ineffective, or was it, as some suspect, never actually administered at all but the money unscrupulously pocketed instead? Or is the curse far more all-embracing than the stovemakers suspect - encompassing not only the clay and the kiln but the potters and, perhaps, even the project too?

If any of you know of a really good Witchdoctor, could you please send us the address - at once.

Sorry, we cannot show a photo of the witchdoctor because as everyone in Africa knows, photos of witchdoctors do not come out. - Ed.