1) Cooling technology 2) Iranian invention
Found on
https://www.crosswordclues.com/clue/yakhchāl
Yakhchāl (یخچال `ice pit`; yakh meaning `ice` and chāl meaning `pit`) is an ancient type of evaporative cooler. Above ground, the structure had a domed shape, but had a subterranean storage space; it was often used to store ice, but sometimes was used to store food as well. The subterranean space coupled with the thick heat-resistant ...
Found on
http://en.wikipedia.org/wiki/Yakhchal
No exact match found.
