What is the best way to douse a charcoal grill? When the heat of a charcoal grill gets too hot, what is the best way to douse the fire; the objective being to lower the temperature without putting the fire out completely?

How much water should be used when burning charcoal in a very primitive grill or pit without a lid or adjustable vents, and how should it be added (poured, sprayed, etc.)?
Add some coals over the hot ones and/or reduce airflow some other way (many grills have slits or vents to control airflow, play with those, close them partially).

Both should reduce heat output (adding coals of course will mean the grill will burn for longer and will eventually heat up again).

I'd not throw water or other liquids on it. Only makes a mess :)