Le Scaphandre de Marseille
Yves Clercin and Charles Daigneault

Dear readers of this history of the "iron" Marseilles diving suit, you may have seen it once in the Marseilles Chamber of Commerce, where it was displayed with the indication "Origin unknown".
It was also shown in the great work "L'Histoire de la Marine par l'Illustration" in the 1934 and 1939 editions with a picture (see right), with the indication "Old metal diving suit for great depths, time and origin not determined" (indication from the Museum of Old Marseille, which closed its doors in 2009).
The diving suit was housed in 1978 at the Centre d'Application de plongée industrielle et de travaux immergés (CETRAVIM, Centre for Industrial Diving Applications and Underwater Work), which opened in 1974 and is now called INPP.
In 1987, it was then moved to the Musée de la Marine et de l'économie in the Palais de la Bourse, after sandblasting to remove dirt and oxides.
The viewing window and the right hand cuff have since disappeared (small picture).

We contacted the Comité du Vieux-Marseille (Old Marseille Committee) via Facebook and learned: 
The diving suit belongs to the Musée du Vieux Marseille, it was housed at the Chamber of Commerce and shown in the exhibition Mémoire à la Mer (Memory of the Sea) at the Musée d'Histoire de Marseille from 29 April 2016 to 28 May 2017, then returned to the Chamber of Commerce, which decided to part with its
 collections. This is how the city of Marseille got back the
 the diving suit, which is now in its archives.
 now in its archives.

Description of the diving suit 
by Robert Sténuit, diver and speleologist, dated 22 November 1998:

The suit consists of four parts, the lower body (trousers), then the helmet with chest and back plate.
The other two parts are articulated pieces that enclose the shoulder with one arm and one of each of the side plates.
The "trousers", from the top of the waist to the toes, are one continuous piece with the two hip and knee joints.

Assembling the wetsuit
The chest and back plates are screwed to the two side plates with 12 fastening clips (6 each at the front and back), through each of which a wing bolt with nut is inserted.
The lower part is fastened slightly above waist level by means of twelve similar bolts, evenly spaced around the 
The lower part is attached to the front, back and sides by means of twelve similar bolts, evenly spaced around the body, via two flanges. The diver enters the lower section feet first.
Next, the helmet with front and back parts is placed on the head, which has to be bolted to the bottom part.
The side parts still have to be screwed on each side and everything has to be tightened.

The joints were sealed with leather strips, impregnated with tallow or gutta-percha (rubber made of natural latex, thermoplastic material, oxidises in air and light, insoluble in water, alcohol and ether, whitish slightly pinkish colour, heat insulator that softens with heat).
In 1843, Werner von Siemens constructed a machine for sheathing leather cables with gutta-percha before coming up with the idea of using gutta-percha to insulate UW telegraph cables.

Helmet: There is an air inlet at the top back of the helmet with a diameter of 3 cm and a second hole (air outlet?), smaller in diameter, at the front of the top part of the helmet. Perhaps this is the hole for a vent valve? Although such a vent makes no sense for an atmospheric hard suit (suit in which the normal pressure of the atmosphere is maintained).

I give the floor to my colleague Charles Daigneault, model engineer:
In my opinion, the Marseille suit is an important prototype, but its condition also leads me to believe that it has actually been used or at least tested in real life.
The mystical suit is indeed very well made. The further I progress in the development of the replica model, the more I am surprised by the complexity of this artefact. The design is great for the time. 
The hip joints for example, it's worth looking at the back to see how they work. And again the geometry of this piece amazes me, the knee joints seem to connect with those of the hips. The whole thing is absolutely not visible in the front photos.
In my opinion, the photo from 1934/1937 (at the top) is the most telling. If you look at the viewing window with its grille, you can see two thin ropes connecting the frame of the window to a fixation above the shoulders of the suit, and you can see the corresponding holes on the top of the fixing brackets very clearly, the hole is clearly visible on both sides in the photos.

In Cabirol and Siebe Gorman it was initially common to connect the sight window to the helmets by a cord or chain to prevent clumsy sailors from dropping these parts into the sea, I infer that this picture shows the original sight window.
Another observation, the soldering or welding of the window attachment and other parts of the diving suit is of the same type as it was in the manufacture of Siebe&Gorman and Cabirol helmets from 1860 onwards.
It does not help much in determining the possible date of manufacture, but this fact leads to the conclusion that the original manufacturer had this technique. 
Was it the "start-up" of a former employee of one of the companies at the time who attempted the diving suit adventure? 
As you know, there is a difference to be made between the "pieds-lourds" suit of the time and a diving suit such as this which operates at 1 atmosphere internal pressure regardless of depth. 
The presence of an air supply hose rules out the use of a closed-circuit breathing apparatus such as those used for diving from 1879 onwards, so there is a good certainty that the suit was made before that date. 
But I can't get it out of my head that the original manufacturer must have had very advanced knowledge of engineering and suits for the time.
The small air outlet for example, the difference in diameter between the air inlet and outlet shows a lack of basic knowledge of gas physics, which would contradict everything. And if it is a vent valve, that would make no sense in an SA (scaphandre atmosphérique - diving suit). But I'm not sure, or if it was rather the air inlet at 1 atm? Then the difference in diameter with the outlet at the back of the helmet would not matter. 
We have to remember that we are still at the beginning of the research, so, trial and error.  We can see it on most patent drawings, many components of these representations are impractical or completely useless, possibly to protect the invention from imitation.

Hypothetically.
we would be dealing with an engineer with a more or less advanced knowledge of helmet diving, enough to be aware of the limitations and dangers associated with printing, living in Marseilles between 18xx and 1900, with forging, welding and machining skills, keeping abreast of the progress of science and industry, no doubt close to the seafaring community so aware that there are business opportunities in salvaging ships and rebuilding harbours and roadsides.
The builder is aware that recycling of exhaled air in closed circuit breathing and removal of CO2 by caustic potash has been known in France, England and Belgium since 1849.

Let us imagine:
In 1870, our engineer, well aware of the science and technology of his time, decides to develop his own SA. 
He knows that there is a telephone in France, Cyrille Duquet made one in 1878. 
He plans a circuit device, designs swivel and ball joints, external manipulators, disassembly/assembly in 4 parts which are essentially a tank.
Is he taking inspiration from Carmagnolle and all the other patent drawings he consulted (see below)? Or is he inventing the whole thing from scratch? That is the question.
Unfortunately, he will only make a prototype, the breathing apparatus and phone will never be installed, but the phone's wire connection is already welded to the top of the helmet.

Why an air supply hose when it is SA with a closed circuit breathing apparatus? Who knows, maybe a safety measure? With the elimination of CO2 we are in unknown territory, if it ever fails there is always a connection to surface air through a non-return valve... which will also never be installed.
Of course, this is all just a bold guess.

Now as to its fate: 
Is it bankruptcy? 
Did the inventor die on the way to success?
Was there a fatal accident or did the prototype "escape" to the bottom of the sea in the end? 
How did the artefact end up in the shed? 
Why is it so neglected and corroded, where did the missing porthole disappear to? 
Was there a lack of money or a scam? 
Oh yes, the mysterious suit is aptly named.
I imagine the brand new diving suit from Marseille, barely finished, 3-mm-thick bronze alloy, the porthole and its protective grille, the pipes and the brass riveted connecting reinforcements, the method of which is well illustrated by the photo of the inside of the helmet, the grey lead soldering clearly visible at the joints of the plates and the porthole, the safety ropes of the latter in their place. 
The two sealed clamps passing through the sleeves look quite menacing. They are used to hold a wide variety of tools, such as the gripping tongs shown, selected according to the work task.
The lifting eye and its attachment sit on top of the helmet, which by the way is not exactly spherical, the clamps with their wing screws are made of brass with red gutta-percha for sealing.

Charles' speciality is the technical side of the suit, mine is the story you will learn about in the next issue of TH in June 2021.
Even though this diving suit has an unknown date of manufacture and provenance, its alloy, the welds used, the installation of the bolts in the period allow it to be identified.
Reference: 
The Musée du Vieux-Marseille, inaugurated in 1912 at the initiative of the Comité du vieux Marseille in Parc Chanot, was moved to the Maison Diamantée in 1967. It closed its doors in 2009. Its collections can now be seen at the Musée d'Histoire de Marseille (reopened on 12 September 2013).

Reference :
[01]"Histoire de la Marine par l'Illustration", 1939		
02] Website Museum History of Diving t1p.en/j231 		 
- M. Xavier Corré , curator of the Marseille Museum 		
- Véronique Raguséo, archivist, department AD 13 
- Annie Philippon, curator Marseille, 
- Marseille Chamber of Commerce 

The photos above come from the archives 
of the Marseille Museum and
Chamber of Commerce and from [02].

More articles: 
Sven Erik Jørgensen: 1-bar dykkeapparater (panserdykkeapparater), DHT 39, 2010 (available in the HTG archives).

Editor: Further examples of tank diving suits: