During the mid-1950s, the Medusa G Due appeared in several diving and spearfishing books.
Ivanovic's 1955
Modern Spearfishing:
The Carriers' 1955
Dive, although this book illustration represents the first-series version of the G 2, the Gigante B (note valves at surface end of snorkels):
Vanderkogel's 1955
Underwater Sport:
Bronson-Howard's 1956
Handbook for skin divers:
In Bronson-Howard's words: "While the majority of masks manufactured today are of standard design, the past three years has seen an increase in popularity for masks which feature built-in snorkel breathing tubes. Numerous models of French, Italian and American design are now on the market. These variations of the ordinary equipment are more expensive, but the added compactness and freedom they give the diver are well worth the difference in price. (Most amateurs, though, will do just as well with the standard models until they have completely mastered the underwater technique.) These masks come in one-breathing-tube and two-breathing-tube varieties. The one-tube model has a flexible rubber snorkel coming off the top center of the mask, or a rigid plastic tube coming off the side. The two-tuber has a plastic snorkel coming off each side of the mask, giving the diver a slightly Mephistophelean appearance when he sticks his head out of the water. The air-intake openings have either a hinged-cork arrangement or a ping-pong ball, which, due to its buoyancy, is forced up into the opening of the tube, thus closing it, when the swimmer is submerged. Unlike the standard mask, breathing is done with the nose, and the mouth is kept closed while the diver is lying face down on the surface of the water."
Small's 1957
Your guide to underwater adventure:
By the mid-1950s, the product was being exported outside Italy. Here are period ads for Cressi States-side:
The Medusa G2 is the twin-snorkel mask in this publicity material.
As for the UK, here's a page from the 1956 catalogue of the British manufacturer Typhoon, which carried some Cressi products:
and one from London-based Lillywhites' catalogue of the same year:
And back in Italy, here's the Medusa G2 in Cressi's 1959 catalogue:
Note the continued availability of the G2 in Medium (B) and Large (C) fittings.
There is little doubt in my mind that the Cressi Medusa G2 gained an iconic status in its time, more perhaps than any other first-generation snorkel-mask. Although no snorkel-masks entered production in the USSR, Soviet diving manual authors were aware of their existence in the West:
Olga Shukova's underwater hunting book illustration above refers to the mask as a "«Двурогая» маска" ("bicorn" mask), a mask fitted with two horns. See it for yourself online at
Снаряжение для охоты под водой.
By the way, this publication isn't the only book-length Russian diving title to be scanned and posted online to be viewed for free. Wouldn't it be nice, particularly in these COVID-19 times of goodwill to all men, if English-language diving journals and books shared their contents online too for everybody's benefit under lockdown?
But I digress. I included the Russian picture above to show (a) how widely known outside Italy the Medusa G2 was in its time and (b) the sinister impact the mask's appearance may have had on some contemporary observers. Shukova herself compares the Medusa G2's twin snorkels to the horns of a wild animal and counsels Russian spearfishers against using the mask if they ever manage to get hold of one. She captions the illustration "«Двурогая» маска — сложная и малопригодная в подводном спорте. Избегайте ее" (“Bicorn” mask: complicated and unsuitable for underwater sport. Avoid it.). So there.
The potential of Medusa G2 users to strike terror in non-snorkellers wasn't lost on western observers either. The 1958 British thriller film "The Snorkel" appears to feature a Medusa G2 as the villain's principal prop:
And here is an American newspaper article from March 1957:
So what the good citizens of Loveland, Ohio, were witnessing did not turn out to be the Little Miami River's very own Loch Ness Monster after all, but simply a couple of young men testing prototypes of the future Skooba-"totes" dry suit manufactured in the So-Lo Marx Rubber works nearby.
The scene above was recreated for a 1959 advertisement:
Note how the figure standing in the stream with the twin-snorkel mask over his eyes, nose and mouth in 1957 has replaced this headgear with a conventional half-mask and double-hose regulator in 1959.