Late 19th Century Merchants: Antifouling Paint Over Copper?

[CDR_Ret]

Pertaining to my research on Matthew Turner's Galilee, I have a drydock photo of her taken on the bow. A very nice reference photo, even if it's in B&W. (See the detail below.)

 

The image is grainy, and the hull below the boot top is mostly in shadow, but there are some curvilinear shadows near the bow that suggest copper sheathing rather than just planking. The right-hand image indicates what I am referring to. But this doesn't make sense, since the bottom clearly has been painted.

 

So, are those lines just unfair hull planking or copper plating that has been painted over? My research turned up a history of antifouling methods, and it claimed that vessels employed in the tropics relied on copper to keep the worms at bay. Since Galilee was used in the San Francisco to Tahiti trade before her employment with DTM/CIW as a research vessel, It's likely that she was coppered.

 

Anyone have thoughts on this?

 

As an aside, what would be the likely color for the bottom paint for a West Coast sailing merchant c. 1890-1910?

 

Terry

 

Edited June 10, 2015 by CDR_Ret

[Jim Lad]

Terry,

 

Painting over copper would be a waste of money.  My take on the photo is that it shows planking below the waterline - if you look closely I think you can see the run of some of the above the waterline planks continuing into the painted area.

 

As for colour, I don't know if your west coast had any particular paint, but is general, I would expect the anti-fouling paint to be a dull reddish colour.

 

John

[CDR_Ret]

John,

 

I suspect you are correct, but I wanted to get a second opinion on the bottom covering. The only two U.S. West coast ships I know of that are contemporaries of Galilee are the Balclutha and the C. A. Thayer, both located at SFMHP. Photos of their restorations show them with the dull red bottom paint. My concern is that in the 1907 photo, the paint looks darker than might be the case with the red lead.

 

Attached are images of NRG sample paint chips for vessels of this era; one is colored and the other in grayscale. Not sure of the color response of the original film, but the grayscale chips suggest a darker color. This is why I could use some Pacific West Coast expertise before making any decisions, granted that this step is pretty far down the pike at this point.

 

Terry

Edited June 11, 2015 by CDR_Ret

[CDR_Ret]

Also, I have in my files this painting by Charles Vickery, who was well known for his accurate rendering of marine subjects. It shows Galilee in the foreground with green bottom paint. The model of the Galilee that was offered by his gallery also shows a green bottom. So I'm inclined to go with a dark green. (The model was more of an approximation than true to scale. There are many discrepancies in the details compared to the actual vessel.)

 

To be completely objective, he also painted Galilee with a red bottom, so perhaps the color doesn't really matter.

Edited June 11, 2015 by CDR_Ret

[CDR_Ret]

New info provided by a photographer friend might be of technical and historical interest.

 

The best black and white film used around 1900 was called orthochromatic film. It was sensitive to blue and green/yellow light but was blind to red light. So red would show up in images as nearly black. Green would be a shade of gray. Based on this information, I suspect the hull in the dry dock photo probably has red paint.

 

Earlier film before 1884 was sensitive to mainly blue and UV light. Panchromatic films sensitive to red light were available in the 1890s, but only on glass plates manufactured in Germany. Based on my grandfather's diaries, and the arduous nature of the geomagnetic field work, I suspect DTM/CIW required the use of emulsion film, which was available only in ortho- or isochromatic form.

 

Attached is another Vickery painting showing Galilee in a red hull.

 

Terry

Edited June 11, 2015 by CDR_Ret

[JohnE]

Hello Terry. I'm late to the party, as usual.

 

In 1900 the West Coast was no different from anywhere else when it came to ship technology. The old SF Engineer’s Gazette and WC Marine Transactions from 1900 show a complete familiarity with contemporary discoveries and practice in NE, NY, and UK. Anti-fouling was a sexy topic back then and California was up to speed on it.

 

For period anti-fouling, the popular metal salts were oxides and chlorides of copper and mercury, along with some admixture of zinc, tin, antimony, lead (even arsenic). The metal salts were suspended in a binder; think they called it varnish back then, but it was basically a ‘relatively’ permeable paint. The metals added some pigmentation to the base but it all depended on what color the base was on how the mix eventually turned out.

 

Then, as now, the antifouling mechanism was the active component leaching through the binder. After a few years (two to four, depending), all the good stuff leaches away and it’s time for a new paint job. Grind away the old stuff with big blocks of volcanic pumice (today’s fart rock), and slather on a new layer of paint. It may or may not be the same composition, so it’s quite reasonable for a vessel to have a different bottom color every few years.

 

I do believe if you paint her bottom in a dull, dingy, green or a dull, dingy, reddish brown, you would be perfectly accurate for at least one period in her life.

 

John

Edited June 17, 2015 by JohnE

[CDR_Ret]

Good stuff, John. That information was the gist of what I was able to glean from several sources. I found the attached document especially helpful. Combined with the film characteristics mentioned earlier, I'm going with the red bottom (when the time comes). At this point, it looks like I need to go back to do some more work on the ship's main rail run and transom moulded outline—a never ending story.

 

Terry

Marine_Antifouling_c 11.pdf

[CDR_Ret]

With respect to my original question, I think I may have found an answer.

 

I learned today that Matt Turner built a two-masted schooner for the Seventh Day Adventists church missionary work at Pitcairn Island. In fact, the vessel was named the Pitcairn. She was launched in 1890 at Benicia, CA, at the same yard and less than a year before Galilee. Since her service was in the Pacific Tropics, and Pitcairn Island (home of the descendants of the HMS Bounty mutineers) is only 7 degrees south of Tahiti, Galilee's intended area of service as a packet ship, it is very likely that both were equipped with copper bottoms.

 

Attached is a good photo of the Pitcairn on the construction ways. Need I say more?

 

Terry

 

P.S.: Considering the timing of Pitcairn's launch, the vessel in the background could be Galilee herself under construction. The rocker bow is distinctive. Wouldn't that be something?!

[trubarth]

Hi Terry. I came across your conversation completely by chance this eve. Am wondering if you were building a model of the Galilee? Am asking because we built two identical HO scale versions of the Galilee (the models depict her research years) and may be able to share some details (such as Galilee's name plate) which we came across by chance at the SF Maritime Museum Library. If so, give me a shout.

[druxey]

Is it possible that what you are seeing in the photograph is thin wood sheathing painted over?

[Jaxboat]

The red came from Red lead pigment. Until recently Lead was replaced by organo tin compounds. Anti-fouling paints now make use of organic compounds which are more biodegradable after leaching (mechanism for fouling control for all). The Italian Navy did use a green anti-fouling paint but I do not know the Chemistry.

Jaxboat

[wefalck]

According to an old textbook on marine engineering (Steinhaus, 1870), antifouling paints were available at that time in a variety of colours, including reddish brown, green, black, white, yellow, and blue. Basically, you just add the pigment of your choice. Their biocide effect was based on inorganic lead and in particular copper compounds. Concerns over heavy-metal contamination in harbour muds and the search for a higher efficacy led to the development of tin-organic compounds. However, these are being phased out since the 1990s, when it was discovered that they act as 'endocrine disrupters', meaning that they lead to malformation in aquatic animals that come into contact with them. The problem is that antifouling paints not only act toxic to things that want to stick to a ship's bottom, but slowly wear off (which is part of the antifouling process) and become dissolved or settle in particles in marine sediments. Here their toxic or endocrine disruptive actions continue. I believe in more recent years antifouling paints put more emphasis on non-stick properties and slow wasting that detaches whatever tries to held a foothold.

 

I gather red(dish brown), green, and black were generally preferred colours, because these resemble the appearance of either coppered or tarred ships bottoms. Muntz-metal bottoms would have looked yellowish to green-greyish, depending on their age. The Austrian navy actually used a pinkish paint on their iron and steel hulls before WW1, btw.

 

Appart from being a waste of money, paint may not stick very well to copper because of the oxide layer that forms rather quickly on its surface. The picture in the first post is not very clear and I don't know anything about the vessel in question, but would it be possible that a protective sheathing of wood was applied on top of the coppering for travelling in areas where there was floating ice ? This sheathing in turn may have been painted.

Edited September 20, 2016 by wefalck

[druxey]

Your take on this is the same as mine, wefalck (see post #10).

[wefalck]

Sorry, druxey, saw it and then forgot it. It came to my mind, because the wooden German research vessel GAUSS (1901) was kitted out in a similar fashion.

[CDR_Ret]

Thanks for the comments, guys.

 

At the time the photos in post #1 were taken, the vessel's charter did not include entry into icebound waters, so no protection against ice floes was needed.

 

The photos themselves don't show enough details of the hull covering to draw any firm conclusions. However, the photo of the Pitcairn in #8 shows the distinctive rectangular blotchy appearance associated with copper plating. The plates themselves are of about the same vertical dimensions as the linear marks in the #1 photos, so I am going copper plates. The darkness of the hull in the old B&W photos is likely due to the color response of the film in use at that time, which wasn't sensitive to the red end of the spectrum.

[wefalck]

Looking again on the images, I think in the area around the stem one sees copper sheathing. What is a bit strange is the somewhat fuzzy waterline that looks painted on. Perhaps she had a reddish boot-topping ?

[grsjax]

Generally copper was laid over a layer of felt saturated with tar.  Could be what you see is the felt/tar layer before the copper plate is applied.  Just a guess.

[druxey]

I think, on close inspection, that I see a line parallel to the painted(?) top of the dark area. Is that the top of what could be the copper?