I have seen it used to cool food in a "coolgardie safe" by evaporation.
Also it can cool rooms with
water being applied to the fabric via strips of cotton sitting in a water bath above and looping down the walls and fastened to the jute.
The water is drawn down by conduction.
From
Coolgardie safe
"The Coolgardie safe is a low-tech food storage unit, using evaporative cooling to prolong the life of whatever edibles are kept in it.
It applies the basic principle of heat transfer which occurs during evaporation of water (see latent heat and heat of evaporation).
It was named after the place where it was invented – the small mining town of Coolgardie, Western Australia, near Kalgoorlie-Boulder."