I saw a citation in a footnote somewhere, but in the three weeks it took for the Design Review: Industrial Design 23rd Annual, 1977, to arrive, I'd completely forgotten why I'd ordered it.
No matter, this insane image of a Makakai deepwater transparent hull submersible (THS) is worth the $2+shipping.
There's a lot less info online that I'd expect for such an awesome-looking rig, but according to Globalsecurity.org, it was developed at the Naval Undersea Research And Development Center [NURAD?] in San Diego:
Two standard spherical hull designs were available; (a) 66 inch outside diameter and 2.5 inch thickness for 600 ft. operational depth and (b) 66 inch outside diameter and 4.0 inch thickness for 1000 ft. depth. The hulls were fabricated by adhesive bonding of 12 thermoformed spherical pentagons, two of which incorporate metallic hatches.I've just added it to my military industrial geodesic sphere government surplus save search list on eBay. Competing bidders, be warned.
Deep Submersible Rescue Vehicle [globalsecurity.org]