The layman term for drain cover (grate) is manhole cover. Say "manhole cover" and images of spies/heros using the underground sewage system popping out of manhole cover in Hollywood films appear.
Historically since that time Man invented the sewage system since the Roman Times to drain water and urban waste away for sanitation purposes, manhole covers (drain covers or grates as we prefer to call them) have been invented out of the necessity in order to avoid people from falling into underground sewage and also prevent large objects from entering the drains which cause choking which eventually can lead to flooding.
Fast forward to the present day, the sewage system is still being employed under all cities around the world. Rather than the crude stone manhole covers the Romans use in the ancient days, today we have special steel reinforced stone gratings that provide the thousand year old function of covering basement floor drain cover of our sewage system.
More than merely a cover, check out Jonite's range of drain covers (drain gratings) here: http://www.jonite.us/products/creative-grates
Going back as far as the Roman times, in ancient Rome Man has started using stone to cover drain covers.
December 23, 2015