water

The need for clean water has been recognized since ancient times.

For example, the Greek ‘father of medicine’ Hippocrates, who lived from 460-354 BC, was among the first to note how water could be purified.

Using what later came to be known as “Hippocrates’ sleeve”, which was a cloth bag, he instructed his follower to strain rain water after it had been boiled.

Without this treatment, he warned that the water would have a bad smell and cause hoarseness.