Did aircraft in that period really use Castor oil as a lubricant. https://www.jstor.org/stable/44643970


, it looks like castor oil would be distinct from petroleum based oils, based on fatty acid content, but I have no idea if it would last in the environment as long.  If it did, it’s preferential use by European aircraft before 1930 might have some diagnostic value

Trace oils in pond sediments can sometimes be detected after  40 years or more according to some journals.  Have sediment samples from around the location where these items been found in the pond been tested for oils/fuel or other chemical contamination that might be related to a plane crash? Sorry if I am suggesting something that was already done

In 2022/23 we tried our damndest to get sediment core samples from the pond for testing.  A paleoecologist at Memorial University in St. John's said that core sample would give us an almost year-by-year compositional history of the sediment.  We had it all set up, but the day we flew the two grad students to the pond to take the core samples, the wind was blowing harder than forecast and the inflatable boat we brought was useless.  Then we came up with a plan to do it in the winter through a hole drilled in the ice. No boat. No wind problem.  We were all set to go when the university faculty went on strike.  By the time that got sorted out, the ice had melted and the paleoecologist bailed because she didn't like all the media attention the project was getting.
In the end, finding unexplained hydrocarbons in 100 year-old sediment wouldn't prove anything and not finding them wouldn't disqualify the hypothesis.  The work we're now doing with the artifacts is proving much more productive.

Trace oils in pond sediments can sometimes be detected after  40 years or more according to some journals.  Have sediment samples from around the location where these items been found in the pond been tested for oils/fuel or other chemical contamination that might be related to a plane crash? Sorry if I am suggesting something that was already done.

Did aircraft in that period really use Castor oil as a lubricant. https://www.jstor.org/stable/44643970

Thanks for your patience. The metallurgist has confirmed my suspicions.  The steel is plated.
That is why the lab results differ from the XRF results.
We were interested in identifying the steel alloy the semi-cyindrical artifact is made of.  We have multiple XRF readings but we wondered if they might be "polluted" by contaminants on the surface of the artifact, so Rick Freeman took a small piece that had broken off the artifact and ground it down until he could see bare, shiny metal. In so doing, he inadvertently ground off the plating, so what the lab analyzed was the base steel minus the plating. What the XRF was seeing is the base metal, plus the plating, plus a layer of paint.

The base metal is carbon steel allied with a little manganese.
Based on averages of the XRF readings, the plating is:
Tin  4.587%
Zinc  1.407%
Manganese 0.458% (minus the manganese in the steel alloy)
Copper 0.394%
Cobalt 0.736%
Chromium  0.129%
Molybdenum 0.125%
Vanadium   0.125%

The paint is:
Silicon   2.633%
Titanium   1.398%
Lead 0.129%
and maybe some of the Cobalt.

"Tin cans" are steel plated with tin as a corrosion inhibitor. They've been around since 1840. The tin plating on this artifact is much more complex than a can of peaches, but its purpose is the same.  The paint added a further layer of protection.  Whether or not it is part of the PL8's water tank, somebody really didn't want this thing to get rusty.
Nevertheless, the portion of this object that was exposed to the pond water corroded completely away over the decades. 
What does that say about the survivability of other un-buried and mostly un-plated steel debris?  No wonder our visual searches have found nothing.

ho Ric, I'd be upset if you had problems with your payroll controller. So I will wait.

BTW i will receive soon a good and lengthy Monography regarding Lorraine Dietrich. You know that this manufacturer first designed sportcars ? Did it ever occur to you that this water tank might have been derived from car apparatus?

Night is coming in Dordogne and i have my little son to care of. I have to tell him the story of a strange big seabird that vanished across the Atlantic some 100 years ago. Take care, I will keep in touch.

As we say in French: 'je donne ma langue au chat'.

LOL! Sorry.  As we say in English, this is way above my pay-grade and I'm trying not to embarrass myself more than usual.

Well Ric, you've sparked my curiosity!

As we say in French: 'je donne ma langue au chat'.

In any case, this common low-alloy steel can undoubtedly be used to make tanks or containers not exposed to particular mechanical or thermal stresses.

From my casual eye, I'd say that only a few factors explain a transformation of the artifact:

- high heat; intense cold;
- exposure to the environment or to a persistent element in that environment;
- the passage of time leading to chemical transformations?

If I'm right, the answer is a lot simpler than that, but I don't want to shoot off my mouth until I have confirmation from the metallurgist.

I'm the one who was 'staggered' when I read today's newsletter.

If the EDS test is correct, and there's no reason to think otherwise, then, except for a measurement error, the previous XRF test would have been altered by some other agent(s) or factor(s).

Firstly, common 1010 steel, which is low-alloy and very soft carbon (class A or Adx ('mild steel') according to the 1920 Houille Blanche classification, would have only 0.30/to.60% manganese as a common element with the artifact. If we disregard traces of phosphorus and sulfur, which give an idea of the steel's purity, then yes, we have a very common steel.

This wouldn't be such bad news, since what I immediately found of the current French version of the '1010' (Arcelor/Mittal) gives us a composition similar to that of the 1920 Class A - 'Houille Blanche' type:

C: 0.08/0.013
Mn: 0.30/0.60
S: 0.035
P: 0.025

https://sections.arcelormittal.com/catalogue/B50/FR

The question of silicon remains. I can't explain the very high levels of this element.

From my casual eye, I'd say that only a few factors explain a transformation of the artifact:

- high heat; intense cold;
- exposure to the environment or to a persistent element in that environment;
- the passage of time leading to chemical transformations?

This steel was most probably in common use in France in the 1920s.

Among the types of use, La 'Houille Blanche' specifies that type A 'extra-soft' is used in particular for “cold-formed sheets and parts
hammered'. Apparently, this is also the case for welded parts.

you have been posting some VERY informative and interesting information from a different point of view and the input is appreciated.

I am seeking for more 1930's metallurgy studies about french spécial steels. l am planning to buy the latest monography about Lorraine-Dietrich manufacturer.

Last, i have the advantage to live not too far from Biscarrosse and the Musée de l'Hydraviation where a very similar E12b 450 cv is exposed. I will try to jump in there one of these days.