GDT has said that the inspiration for Johann's suit in HELLBOY II is from Jules Verne, so I thought I might share some pictures from the web of Verne-inspired art and illustrations so you can see how they compare.
Here is our HELLBOY II Johann:
And here is a painting by watercolorist Milo Winter (1888-1956). This painting first appeared in a 1922 juvenile edition of 20,000 LEAGUES, published by Rand McNally & Company.Next is some original concept art from Disney's 20,000 LEAGUES movie starring Kirk Douglas. And here is Disney movie poster: And a helmet from the movie itself:
And if you want to see something really cool, check out this site, where a guy built a working version of the Nautilus suit!!