58 Mr. Williams's Account of making Ice at Benares. 
water is taken from a well contiguous to the spot. New 
vessels, being most porous, answer best. 
It is necessary that the straw be dry ; when it becomes wet, 
as it frequently does by accident, it is removed, and replaced. 
I have observed water which had been boiled, freeze in a 
china plate ; yet having frequently placed a china plate, with 
well-water, among the unglazed pans on the straw beds, I 
found that when the latter had a considerable thickness of ice 
on them, the china plate had none. I have also wetted the 
straw of some of the plats, and always found it prevented the 
formation of ice. The air is generally very still when much 
ice is formed ; a gentle air usually prevails from the south- 
westward about daylight. I had a thermometer among the 
ice pans, during the season of making ice, with its bulb placed 
on the straw, and another hung on a pole gj feet above 
the ground ; and commonly observed, that when ice was 
formed, and the thermometer on the straw was from 37 to 
42 0 , that on the pole would stand about 4 degrees higher ; 
but if there was any wind, so as to prevent freezing, both the. 
thermometers would agree. 
I shall offer no opinion respecting the causes of ice being 
formed when the thermometer is so many degrees above the 
freezing point 5 but hope the subject will be elucidated by 
some more capable person. 
I am, &c. 
Benares, 
March 25, 1792, J» LL. WILLIA1VIS, 
