What is Perspiration

It's not really sweat that cools you down on a hot day, it's the evaporation of sweat.
For surface liquid molecules to leave into the air as gas, they must overcome the force that binds them together.
In the process, they use of energy in the form of heat, drawing this heat from the liquid surface.
The water that remains—the perspiration left on your skin, that is—is cooler.
Why is it you can sweat away sultry afternoon without feeling relief?
The thick, saturated air has little room to receive escaping liquid particles, so they stay put.
You're wet, but not cool.
In very hot climes, it is common on a sweltering day to consume hot liquids, such as soup or tea.
The reason is to facilitate perspiration, which when it evaporates makes you feel cooler.