Transparent aluminium is a constuction material much stonger and much lighter than its predecessor, plexiglass. A 1-inch thick sheet of transparent aluminum, measuring 60' x 10', is capible of withstanding the pressure of 18,000 cubic feet of water, which can be used in place of a 6-inch thick sheet of plexigass.
Dr. Nichols of the San Francisco based, Plexicorp, acquired the formula for transparent aluminum in 1986 for a mysterious engineer from Edinburgh, known as "Professor Scott". In exchange for the formula, Dr. Nichols provided enough plexiglass to "Professor Scott" to construct a giant whale-tank in the cargo hold of the stolen Klingon Bird of Prey. (Star Trek IV: The Voyage Home)
- In an alternate timeline, transparent aluminum was invented at a date much later than 1986.
- In 2004, 3M announced that a process for making "Alumina Glass" (Transparent Aluminium) has been created, and the technology looks very promising. Here is an article: Transparent Aluminium