{"id":4229,"date":"2021-05-03T12:53:53","date_gmt":"2021-05-03T05:53:53","guid":{"rendered":"https:\/\/bluejapan.org\/fr\/?page_id=4229"},"modified":"2021-05-31T18:47:02","modified_gmt":"2021-05-31T11:47:02","slug":"modern-diving","status":"publish","type":"page","link":"https:\/\/bluejapan.org\/fr\/culture\/japans-diving-culture\/history\/modern-diving\/","title":{"rendered":"Modern Diving in Japan"},"content":{"rendered":"\t\t
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Culture<\/h1>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Elements of Japanese Diving History\n<\/h1>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Modern diving<\/h1>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
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Beyond its traditional freediving culture, an island-nation like Japan was naturally interested in the potential of recent technological developments for underwater activities, allowing more efficient seafood and pearl collection, ship repairs and also salvage missions.<\/p>

The 19th<\/sup> century was one of great inventions, and of the first standardisation of hard-hat<\/em><\/a> heavy diving equipment.<\/p>

Despite the (relative) isolation imposed by the Shogunal authorities<\/a> until the mid-19th<\/sup> century, Japanese industrialists and the military were well aware of recent technological developments, and the government started importing diving equipment as soon as 1857 (the sakoku <\/em>isolation policy gradually edored after 1853)\u00a0 – the first officially recorded use of hard-hat diving equipment was in 1866, by Mankichi Ueda<\/strong>, to repair an English ship.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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The Japanese Imperial Navy also ordered and used the Rouquayrol and Denayrouze<\/em> underwater breathing apparatus<\/a>, which was first commercialised in 1865<\/strong>, as did other navies worldwide.
As lightweight device, with its highly recogniseable snout half-mask, it was one of diving’s first commercial success.
It was also, highly innovative, being a demand membrane regulator system, that could be used as a self-contained unit.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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Rouquayrol\/Denayrouze regulator apparatus<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Image source: www.midilibre.fr<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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After the Meiji Restoration of 1868, hard-hat devices started being imported on a private basis –
Mankichi Ueda, imported 10 English-made hard-hat diving kits for commercial use in 1872, for example.<\/p>

It was not long before some hard-hat diving derived kits were manufactured in Japan as well, especially after 1877, when abalone culture took off across the country and increased the demand.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Image source: The_Journal_of_Diving_History_86_2016<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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Japanese-made Kimura diving helmets. Most Japanese bonnets models were based on Siebe design, and handmade, well into the mid-20th century…<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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The other major impulse boosting demand for diving equipment and divers was the Japanese involvement in the development of artificial pearl culture<\/a>, a primarily Japanese invention.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Cultured pearls and pearl farming techniques were developed in Kansai in the late 19th<\/sup> century, along with the establishment of large aquaculture farms in western Japan, such as Toba\u2019s Mikomoto Pearl Island.<\/p>

Japan helped develop the cultured pearl industry, and exported its know-how, and divers.
By the 1920, the majority of divers working in pearling were Japanese.<\/p>

On the right, a Japanese hard-hat pearl diver, who as working on Thursday Island, in the Torres Strait (Queensland, Australia).<\/a> <\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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Image source: State Library of Queensland<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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Japanese pearl \/ abalone diver, 1905
<\/strong> Image source: wikipedia<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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Pearl cultivation requires introducing an irritant into the oyster, then placing the oyster in a safe place and monitoring it, before finally harvesting.<\/p>

While hard-had divers were commonly used, this new technical process dramatically boosted the demand for ama<\/em> freedivers, as they turned out to be the most useful for the job, especially for large scale operations.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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Furthermore, because of these important developments, the island-nation of Japan also became, in the late 19th<\/sup> to early 20th<\/sup> century, a place of technological innovation for diving equipment.<\/p>

A pair of low-volume diving goggles, called m<\/em>\u012bkagan<\/em> (\u30df\u30fc\u30ab\u30ac\u30f3)<\/a> was developed in Okinawa in 1884 by Yasutar\u014d Tamagusuku, for instance, and then goggles with a pressure equalising device were also pioneered, allowing for deeper dives.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Image source: divingfan.net\/diving-history<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Image source: Emily Tucker <\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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Image source: Yoshinobu Nakamura 1962\/63<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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m<\/em>\u012bkagan<\/em><\/a> goggles & pressure equalising goggles.<\/h6>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
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As mentioned, hard-hat equipment was already available, and naturally put to use in pearl cultivation.
Yet this was not without some issues…<\/p>

The heavy hard-hat diving gear offered divers access to longer dive times and deeper depths, but depth was not crucial in pearl cultivation, which is mostly done in the shallows.<\/p>

Longer dive times were attractive, but as a drawback, diving equipment was expensive<\/strong>, and called for a surface crew<\/strong> to help the diver kit up and then to support him underwater, which increased costs and drastically limited the work-force.
And the hard-hat divers, with such heavy equipment were also relatively clumsy<\/strong>.<\/p>

Which is why ama<\/em> freedivers were amply used.
They were plentiful, nimble and efficient.
However their effficiency was radically reduced by the brief duration of the dives, with an average of 1 minute spent underwater, followed by 60 second recovery on the surface…<\/p>

This situation led to the\u00a0 development, in Japan, of new diving equipment, aiming to bridge the gap between the ease of freediving and the efficiency of hard-hat diving, but with far less constraints.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Enter the Ohgushi Peerless Respirator<\/h1>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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It is in this context that in 1918 pearl entrepreneur Riichi Watanabe<\/strong>, along with machinist\u00a0 Iwao \u014cgushi, <\/strong>manufactured a fully operational self-contained underwater breathing apparatus, that could be used tethered, or autonomously, not connected to the surface.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Image source: jsuga.exblog.jp<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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What’s in a name?
<\/strong>
Out of the two primary inventors, Mr. \u014cgushi\u2019s name is something of a mystery.<\/p>

He gave his surname to the Ohguchi Peerless Respirator<\/em><\/strong> device (the family name was then transcribed Ohgushi<\/em>, with an h<\/em> used to indicate a long o <\/em>sound), but his personal name is less clear.
He is called Iwao \u014cgushi \u5927\u4e32\u5ca9\u5c3e<\/strong> in most recent Japanese sources,<\/a> (other example here<\/a> and a rather definitive here<\/a>).
In older sources, however, another personal name is sometimes given, \u5927\u4e32\u91d1\u8535<\/strong><\/a>.
This name is itself mostly transcribed with a rather uncommon reading as Kanez\u014d \u014cgushi<\/em> in English language sources, especially in Nyle Monday’s influential research<\/a>.
Yet if it was this indeed his personal name, Kinz\u014d<\/em> \u014cgushi <\/em>would be the most common and natural reading.<\/p>

We’ll follow the most recent output by authoritative Japanese sources,<\/a> and like them call the inventor Iwao \u014cgushi \u5927\u4e32\u5ca9\u5c3e.<\/strong><\/p>

According to them, Mr. Iwao \u014cgushi was still active and alive in the 1970s, and was interviewed by Marine Diving magazine<\/strong>, for an article published in the magazine’s issue 10 of July 1971.<\/p>

\"\"<\/a>
\u5927\u4e32\u5ca9\u96c4\u6c0f Mr. Iwao \u014cgushi, who patented the mouth-operated demand valve system in 1920.<\/figcaption><\/figure>

The Ohguchi Peerless Respirator<\/em> breathing apparatus was patented in Japan (first version in 1918 then in 1920 \/ Taish\u014d<\/span> 9) and also abroad, and was later used\/adapted in different places, notably by the Soviet navy, on a well-documented salvage mission.<\/p>

It is interesting to note that another very similar design, but with a full face mask, the Yamamoto respirator <\/strong><\/a>or (Yamamoto-shiki sensui no tomo <\/em><\/a>literally the Yamamoto-design diving-companion<\/em>) was also patented at the same time in Japan. Although less well known than the Ohgushi design, it was actually more commonly used, supposedly because the demand valve mechanism, though similar, was more confortable than on the original Ohgushi design…<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Image source: jsuga.exblog.jp<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Yamamoto’s S<\/em>ensui no Tomo <\/em>respirator<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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As it is often remarked, with a touch of national pride:<\/p>

1918 is indeed almost 25 years before Jacques-Yves Cousteau and Emile Gagnan patented, in 1943, the famous Cousteau-Gagnan self-contained underwater breathing unit,<\/strong> which, presented in this way, does make the device seem quite revolutionary.<\/p>

Alas…
Diving history is complex, as is the timeline of diving-related inventions, especially the period from the mid-19th<\/sup> century to the mid-20th<\/sup> century.<\/p>

And contrary to what might have been written by some eager for Japan to take a leading position in the development of self-contained breathing devices<\/a>, the patented Ohguchi Peerless Respirator<\/em>, <\/strong>while certainly innovative and unique, is not the first pressure regulator-based breathing system, nor is it the first self-contained device.<\/strong><\/p>

The Japanese unit only one of multiple inovative inventions <\/strong>which predated the development of the Cousteau-Gagnan<\/em> scuba model.<\/p>

Focusing exclusively on the Cousteau-Gagnan design is to forget that it is itself to be placed in a continuity of successive inovations and inventions which began in the 19th century, along the following rough timeline:<\/p>

[ Rouquayrol\/Denayrouze unit\u00a0 > Maurice Fernez unit > Watanabe\/\u014cgushi\/Kataoka “Ohgushi” unit > Fernez\/Le Prieur unit > Le Prieur unit > Georges Commeinhes GC 43 > unit Cousteau\/Gagnan CG 45 unit ]<\/em>
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This is list is schematical and highly reductive, as many other underwater breathing systems were conceived and experimented (including the Dr\u00e4ger<\/em><\/span> units, other rebreathing devices and other less well-known devices such as the Cabirol<\/em>, or the Desgrez<\/em> and Balthazard<\/em> for instance.. for instance), all in roughly the same timeframe.<\/p>

Most of these devices derive from breathing apparatuses initially designed for use in a mining context<\/strong>, as\u00a0 development of modern mining techniques in the 19th century led to safety and environmental concerns (another famous example being the development of hyperbaric science, which started off as a studies of caisson<\/em> illness…).
A good ressource on the subject is Vianney Massenet’s Ph.D thesis on the development of recreational scuba diving<\/a>, which is accessible here<\/a>, but published in French only…<\/p>

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Extract from Vianney Massenet’s Ph.D thesis, timeline of inventions leading to recreational scuba diving, listing from left to right: invention dates, inventor name, profession, location and device.<\/figcaption><\/figure>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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That said, Watanabe\/ \u014cgushi’s Japanese scuba unit model is nonetheless particularly interesting in its design, which included true technical innovations.<\/p>

It also stands out by its primary function and purpose, directly linked to the development of the pearl industry and its requirements for flexibility, and, as such, definitely deserves its place in world diving history.<\/strong><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Design and innovations of the Ohguchi Peerless Respirator<\/h1>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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To describe the unit briefly, it is an underwater breathing device that could be used connected to a surface compressor<\/strong> (a patent machine, with 4 cylinder reciprocating hand pumps capable of offering 200 bar of pressure) or autonomously as a self-contained unit<\/strong>, with the diver wearing one or two back-mounted compressed air cylinders.<\/p>

The standard cylinder was said to contain 1000 litres of air at 150 bar<\/strong>, making it a roughly 6.5 litre tank, and was fitted with a pressure gauge.<\/p>

The Ohgushi unit went through different phases of development and patents.<\/p>

In its most advanced design, the device was functioned through a manually activated demand valve system, controlled by the diver\u2019s mouth<\/strong> (airflow valve opening being controlled by teeth pressure).
The system design implied that the diver had to\u00a0 breathe in through the nose<\/strong>, which was enclosed in a facemask fitted with an air inlet.<\/p>

Airflow strength was proportionnal to the pressure applied (stronger teeth pressure = wider valve opening = stronger air flow), and the flow could be calibrated to the diver’s requirements by adjusting a T-shaped screw prior to diving.<\/p>

The mask itself was other similar to a modern round diving mask, covering both the eyes and the nose.<\/p>

After inhaling through the nose, the diver closed the air inlet by releasing teeth pressure and exhaled through the uncovered mouth.<\/p>

However, more than the regulator design, which was still a “manual” system, albeit teeth-pressure controled, and far from the first,\u00a0 we believe the unit stands out by the use of modern-style, high-pressure compressed air diving cylinders.<\/strong>
Previous units that could be used self-contained, such as the Rouquayrole-Denayrouze used a back-mounted horizontal steel cylinder, but the pressure was not very high, allowing for a much shorter autonomy.
Compressed air had been around for a while, yet compressed air cylinders were relatively new.
We do not know the source of the Ohgushi or Yamamoto device’s air cylinders. Roughly at the same time, when Yves Le Prieur created also a device using high-pressure air cylinders, he used Michelin air cylinders designed to fix automobile tyres…<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Ohgushi device, with the teeth-pressure controled demand valve visible under the mask<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Image source: The_Journal_of_Diving_History_86_2016<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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This combination of a half-face mask and a mouth-controlled demand valve <\/strong>(which freed the hands of the diver), is quite unique.<\/p>

Going into more details, the Ohguchi Peerless Respirator<\/em><\/strong> had an oval mask made of rubber with a clamped face glass, covering the eyes and the nose, similar to early round diving masks.
It had a hooked harness acting as a mask strap at the back of the head.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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A standard poppet valve was connected to the outside structure of the mask, aligned with the diver\u2019s exposed mouth.

Air flowed from the air source used, either the surface pump or the back-mounted cylinder(s), into the valve\u2019s inlet.<\/p>

The valve\u2019s outlet was connected to an external tube, itself connected to an inlet on the side of the face-mask.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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Image source: jsuga.exblog.jp<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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Image source: divingfan.net\/kind-of-diving<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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On the rear of the demand valve, 2 levers are held between the teeth of the diver, one is fixed and the other one mobile.<\/p>

To open the valve and get air, the diver needed to clench his teeth, which opened the valve and let air flow to the mask\u2019s air inlet.
The diver would then inhale the air through the nose.<\/p>

To exhale, the diver unclenched his teeth, which shut the valve, and then exhaled through the mouth.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Image source: The_Journal_of_Diving_History_86_2016<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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To summarise, the “Ohgushi’s Peerless Respirator<\/em>” could be used an autonomous (self-contained) or surface-connected device, and supplied air to the diver through a demand valve regulator, activated by mouth movement (teeth pressure on levers), which effectively freed the hands for underwater work.<\/p>

This level of autonomy might seem completely ground-breaking in 1918, but only if we ignore other technological advances<\/strong> of the 19th<\/sup> to early 20th<\/sup> century, to only focus on the Cousteau-Gagnan membrane-based demand regulator.<\/p>

The Ohgushi’s Peerless Respirator<\/em> actually fits in a continuum of similar devices, which were already known in Japan and probably influenced its conception, and stands out mainly by the originality its teeth-pressure based demand mechanism and eye and nose covering facemask.
A detailed article on the Ohgushi device can be downloaded here<\/strong><\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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