both for the mixer, and for those sent to help us finish
As is evident from our 'first attempt' at a very large dome (18 ft in diameter and about 21 ft high) - many hands made for an odd looking structure. It is a testimony to the strength of the material that it worked anyway. Our later dome in Darfur is much prettier. This one will be much more beautiful after it is plastered and the doors and windows evened out. The lime and 'cotton soil' mix for the first 3/4 of the dome actually worked. The material was a bit unwieldy and sticky - making it difficult to fill the sandbags - but nevertheless, if that is the only material available - it can be used! Our initial batches of lime were not very active, so we used 15%... After we found truly active lime, we reduced it to 5% and mixed the cotton soil with rough and smooth sand. These materials are readily available and also quite cheap.
We worked about 10 days on the Khartoum dome - [well, Hooman did, - and I was off doing things like renewing our license, asking for permits to Darfur and other such support matters] and we took off for Darfur. We left the finishing touches for Khartoum in the capable hands of Mohamed, 'Aderope', the newly trained laborers, and several of Hooman's student fans. We were stoked to see it finished when we got back!
Many thanks to all of you.
The Darfur Hedgehog that we found: