A Brief History of Diving (before 1943)

[Compressor]

The narration on the Cousteau video is something else. It showed that at the time, there was some fear of the sea and what was under the surface. Perhaps its just Hollywood exuberant attempt to keep the viewer attached to the screen. They did not know that the video will show up on SB where we all enjoy it so much.

 

[John C. Ratliff]

Compressor,

The narration on the Cousteau video was not "Hollywood," as it was done in war-time occupied France, and originally in French. Periscope (a Navy production) may have added some there, but again, not "Hollywood." There was a lot of fear about the undersea environment, as nobody had ever seen it, and we had wood engravings at that time (around the time of my birth) showing all sorts of weird sea monsters and ships sinking. We've evolved since then.

In answer to an earlier question about ease of breathing and the double hose regulator, Bill Barada, in his manual Let's Go Diving--Illustrated Diving Manual (published by U.S. Divers Company, 4th Printing, November 1965 and copyrighted in 1962) published this table titled "Two-Hose Regulator Verses Single-Hose" on page 29.

As you can see, for a high-performance double hose regulator, positioning is the key to good breathing characteristics. While the breathing characteristics of any regulator matter a lot, so does the position of the demand valve. Next dive, get into a vertical position with your single hose regulator, and look up at the surface and breath. You will find that your very high-performance regulator breaths rather hard in that position. That's because you need to overcome a 12 inch head of water between the regulator diaphragm and the center of your lungs. The same goes for a two hose regulator. In the below photo by Sid Macken, you can see me in Big Cliff Reservoir with a very high performing double hose regulator, but note that you cannot see the regulator itself. That is because it is down, an my back between my shoulder blades, where it is supposed to be.

SeaRat

 

[emoreira]

Yes, I have seen that first regulator. Actually, Cousteau had his first film using this first aqualung, which was much different than the first DA Aqua Lung I show above. It was quite an apparatus, taking two people to transport on the surface. Here's the film:


I have a photo of that first regulator in one of Cousteau's books, and I'll see whether I can find it and scan the image.

SeaRat

I don´t know where this film was made, but it should have been taken in the Caribean, as the diver is using no wetsuit.
Another thing to note is the short fins, no BCD (it didn´t even exists in that time), large low pressure multiple tanks.
A stunning fact is the fast kicking and ascending faster than his own bubbles.

 

[Compressor]

Compressor,

The narration on the Cousteau video was not "Hollywood," as it was done in war-time occupied France, and originally in French. Periscope (a Navy production) may have added some there, but again, not "Hollywood." There was a lot of fear about the undersea environment, as nobody had ever seen it, and we had wood engravings at that time (around the time of my birth) showing all sorts of weird sea monsters and ships sinking. We've evolved since then.

In answer to an earlier question about ease of breathing and the double hose regulator, Bill Barada, in his manual Let's Go Diving--Illustrated Diving Manual (published by U.S. Divers Company, 4th Printing, November 1965 and copyrighted in 1962) published this table titled "Two-Hose Regulator Verses Single-Hose" on page 29.

View attachment 430317

As you can see, for a high-performance double hose regulator, positioning is the key to good breathing characteristics. While the breathing characteristics of any regulator matter a lot, so does the position of the demand valve. Next dive, get into a vertical position with your single hose regulator, and look up at the surface and breath. You will find that your very high-performance regulator breaths rather hard in that position. That's because you need to overcome a 12 inch head of water between the regulator diaphragm and the center of your lungs. The same goes for a two hose regulator. In the below photo by Sid Macken, you can see me in Big Cliff Reservoir with a very high performing double hose regulator, but note that you cannot see the regulator itself. That is because it is down, an my back between my shoulder blades, where it is supposed to be.
View attachment 430316

SeaRat

My apologies SeaRat for having the wrong facts, I appreciate your detailed response, finding it very educational. I do not follow the 12 inch example as the difference between head up and head neutral is about 2-3 inches. When our diagram moves down, it’s creates negative pressure and entrails air fro the regulator. The regulator does not create positive pressure ventilation unlike intubated hospitalized patients on a ventilator.

There is no doubt that breathing with face up is more difficult. I am not sure why.

 

[John C. Ratliff]

Akimbo,

This is a photo of the book, The Ocean World of Jacques Cousteau, Man Re-enters the Sea (The World Publishing Company, Copyright 1974, Jacques-Yves Cousteau, page 77). It shows what Cousteau states is the first regulator, and it looks like it too. Note the copper wire holding the hoses onto the mouthpiece and regulator box, and the regulator box itself looking home-made from car parts. In the chapter heading on page 76, "Getting unto Thyself," the last paragraph states "...Ten years later, another Frenchman, Georges Comheines, tested a semiautomatic regulator attached to a compressed-air container. It was a modified version of an air-breathing apparatus used by firemen in toxic atmospheres. Unfortunately, Comheines died during one of his dives. By that time, Emile Gagnan and I were already working on our..." The rest of this text is on the page I scanned. The photo shows Frederick Dumas with the classic cousteau three-cylinder aqualung and commercialized DA Aqua Lung regulator. But the regulator above that photo looks to be the original regulator Cousteau dived in those original dives.

SeaRat

 

[Akimbo]

It shows what Cousteau states is the first regulator, and it looks like it too.

That's really interesting. I seem to recall reading that the housing was made from Bakelite. I wonder if that part was "borrowed" from another product or if Émile Gagnan was able to make it in his shop with some type of inexpensive tooling? I have never used Bakelite but it doesn't sound like you can cast it in a wooden mold.

 

[Compressor]

Thank you SeaRat and Akimbo. So much history to read and enjoy. I ordered the book; surprised it was available on Amazon )). Keep it flowing.

I'll try to find some videos on this too later in day.

 

[John C. Ratliff]

... I do not follow the 12 inch example as the difference between head up and head neutral is about 2-3 inches. When our diagram moves down, it’s creates negative pressure and entrails air fro the regulator. The regulator does not create positive pressure ventilation unlike intubated hospitalized patients on a ventilator.

There is no doubt that breathing with face up is more difficult. I am not sure why.

You are correct in that the regulator does not "create" positive pressure. It puts out air at precisely the same pressure as the surrounding water. This is known as ambient pressure. But, you have to look at the diagram again.

If you'll look at the diagram of the diver in a vertical position, the difference between where the regulator is located and the center of his/her lungs is over ten inches. The regulator put out air at ambient pressure of that space, horizontally. But the center of the lungs is some 10-12 inches below that space. Therefore, there is a negative pressure of 10-12 inches (if I look up, I can hold my ruler with one end at the center of my mouth, and the other at the center of my lungs). We know that in sea water there is a 0.445 psi difference per foot of water pressure (one atmosphere is 14.7 psi, and represents 33 ft of sea water; 14.7psi/33ft = 0.4455 psi/ft). That means that there is a negative pressure on your lungs of 0.4455 psi, and we have to overcome that pressure in order to activate the regulator when vertical looking up with a single hose regulator. However, with a double hose regulator, with the regulator between the shoulder blades, there is only about three inches of difference between the center of our lungs and the regulator, and so the pressure is much less (0.1114 psi, to be exact in sea water). This is also why the old use of a snorkel greater than about a foot will not work, as the lungs cannot pull that much negative pressure to breath, and the drawing by Vegitius would not work--too much water pressure to breath under these conditions.

SeaRat

 

[Compressor]

Thank you John . I appreciate the article.
What is the difference between performance of the double hose reg versus a single hose one. ie: You need to know the cracking pressure, don't you?

The human diaghram muscle can generate enough pressure to overcome minute cracking pressures. I am a little sick so will answer more once I feel better.

 

[happy-diver]

Recovering another magnificent Akimbo thread from the annals