There was a time when there were no wetsuits made of expanded neoprene; in fact, this material was an innovation invented in 1951 by American Hugh Bradner. La Spirotechnique was the first to use it to make tight-fitting diving suits, which finally replaced the valveless dry suits made of canvas rubber. These had a bag-like fit and offered zero comfort, as they couldn't be compensated for, and after a few meters of descent they began to hurt like hell, tightening around the body. So freedivers, then all hunters armed with spearguns, stayed away from them and resorted to thick, felted wool sweaters that were better than nothing.
Then someone thought of seals and the freezing Arctic seas in which they live so well, protected from the terrible cold of those latitudes by their thick layer of blubber. And here is the idea of preparing for divers a greasy, viscous and sticky cream to be applied generously all over the body as an insulating substance alternative to natural fat.
The general concept was sound, but a millimeter or two of cream couldn't quite achieve the same effect as four fingers' worth of body fat. So, after some initial success, the "Foca" fell into oblivion.
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