Re: Viewports gobbed on with silicon

[Ray Keefer <Ray.Keefer@eng.Sun.COM>]

Hi,

> >.... if the view port does not fall off while you are hauling it to the 
> >water, it will surely pop out from the air pressure inside.  
> 
> Aha! No pressure!
> 
> >If the viewport were placed inside, it would probably work. 
> 

Well there is actually a pressure diffential. The pressure on the inside the
viewport will be at the water pressure at the base of the drum, i.e. where the
air and water meet. The water pressure on the outside of the viewport will be
the water pressure at the depth of the viewport.

Since the water pressure at the base of the air column will be larger then
the pressure at the water column where the view port is there will be a 
slightly larger pressure from the inside on the view port. How much difference
depends on how tall the air column is.

I would feel better if the window was secured some how. If the window 
you might panic before getting clear of the drum.

Regards,
Ray