When did cowl vents come into use, and what preceded them?
If you look at pictures of the SS Great Britain you can see that it has no cowl vents. It is a steamship so air has to get from outside the ship to the boilers through a hole somewhere in the deck. The only explanation I can come to is that one of the companionways led into the boiler room, meaning that the doors had to be left open when the ship was at sea. Anyone have any better knowledge or ideas?
I am building a model of a steamship built 15 years after the Great Britain, and information about the former suggests it also did not have cowl vents.
