>>482283Obviously boiling for cooking has been around for a long time estimates range even as far as 200k-500k based on archaeological finds.
and Sanskrit scriptures mention boiling, with hot stones and metal and filters as purification methods but they where done for taste. since in their understanding " good taste = non sick-making water" , this went as far as thinking herbs like tea made water save.
people thought miasma was the cause for sickness. for them the idea of a 100 year old well suddenly becoming the cause of a cholera epidemic was outlandish. Until people like John Snow proved it.
Tl:dr
was water boiling around - Yes!
Was it used intentionally for water treatment? No!