Silent footage from 1923 of a USAS plane dropping a ‘curtain’ of titanium tetrachloride creating a hanging curtain of opaque gases to conceal ships.
This is where the phrase originates.
The technique would go on to be used in WW2.
Silent footage from 1923 of a USAS plane dropping a ‘curtain’ of titanium tetrachloride creating a hanging curtain of opaque gases to conceal ships.
This is where the phrase originates.
The technique would go on to be used in WW2.