Spectacular Series of Dutch Submarines from 100 years ago

The originals are available in color now.

This series about Dutch submarines nearly a century ago (so far) consists of four parts:

Part-1: Submarines on exercise in 1928 in color:

Part-2: Torpedo tests in 1923 in color:

Part-3: Submarines in Indonesia in 1938 in color:

Part-4: In Amsterdam, Construction, Launch O-10 & Waterplane:

thanks to Subsim member Polundra!