Friday, April 2, 2010

Palaeoeskimo Skin Processing Experiments

Sinew and Baleen hafted scrapers
I started using the stone endscrapers on the hooded seal skin first thing yesterday morning. In general, I wanted to get a feel for using chert endscrapers to clean a skin, and specifically I wanted to test the durability of sinew versus baleen hafting material. I had one endscraper hafted in a wood handle with sinew and hide glue and a second hafted with baleen and hide glue.

The used sinew hafted scraper
The sinew scraper became loose in the handle after 23 minutes of scraping. The lashings started to soften and the scraper started to wiggle like a loose tooth, although after another 8 minutes of scraping (31 minutes total) it was still secure enough to continue working. The lashings became slightly more flexible, but it really didn't impede the function of the tool.

The oil saturated baleen hafted endscraper
The baleen hafted scraper became loose after 49 minutes of scraping. It lasted more than twice as long as the sinew hafted scraper and after another 10 minutes of scraping (59 minutes total) it was still working. The hard socket formed by the baleen has still not become flexible, as the sinew haft did, and although the glue was no longer holding it in place the haft was still as firm after an hour of scraping as it was at the beginning. Unlike the sinew hafting, where the binding material itself started to become flexible after 23 minutes, it was the glue alone in the baleen haft that was undone by the greasy work after 49 minutes. The baleen socket is still rock solid after almost a full hour of messy greasy scraping.

Scraping with the Palaeoeskimo reproduction endscraper

Regluing the scrapers using seal blood
Since both scrapers popped out of their bindings so neatly, I cleaned them up at the end of the day and reglued them using some of the seal blood, yet another cool traditional use for seals. Lori collected some of the blood from directly out of the seal's heart at the necropsy. Its really sticky - in fact, when you are eating uncooked seal you have to be careful not to glue your teeth together!

The fat and hide
Sinew vs. baleen was the specific question that I wanted to look at, but in general terms, I realized that chert endscrapers are still a bit of a precission tool for the stage of skin working that this pelt is at. I've cut off the thick layer of fat, which weighed in at whopping 125 pounds! Think about that for a minute, that's just the fat that was clinging to the hide when the seal was skinned. One hundred and twenty-five pounds is the equivelant of one whole 105 pound Pamela Anderson PLUS a 20 pound bucket of lard.

video


Slate ulu pressing out the grease
But the fat and connective tissues that are still clinging to the underside of the skin are saturated in grease and the sharp edged scraper can't start actually scraping until after that grease is removed. Most of what I did with the little endscrapers was squeegeeing out the grease from the skin. I briefly tried a metal ulu and the wider blade did wonders - where the endscrapers were removing the grease a tablespoonful at a time, the ulu was pressing it out by the cupful.

I took a break and did some more reading. Priscilla Renouf and Trevor Bell wrote a paper outlining Dorset Palaeoeskimo Skin Processing at Phillip's Garden, Port au Choix, Northwestern Newfoundland. In it, they identified a set of slate artifacts called tabular scrapers that look to be designed specifically for degreasing hides. I didn't have any of the tabular slate scrapers made up ahead of time but after spending a couple hours pressing out the grease from the hide using the little chert endscraper they seemed like a pretty good idea.

Rough, unhafted tabular slate scraper
I made a rough, unhafted version of the bevelled-edged tabular scraper and tried it alongside a slate ulu reproduction that I found in a box in the basement. It worked great. I probably could have accomplished in 15 or 20 minutes with the tabular scraper what it took me an hour and a half to do with the endscrapers. Next time I clean a skin though, I'll make one with a handle. This is the only tool that tired out my hand from having to pinch it between my fingers.

Degreasing with the tabular scraper

Degreasing with the slate ulu
Next to the metal ulu, the ground slate ulu and tabular scraper were the best suited to degreasing the skin. You can press a wide swath and the grease pours out of the skin. In some ways, I even preferred the slate ulu to the metal knives and I wish that I would have started using it sooner.
Shiny happy ulu
The sharp slate is just as effective in slicing through the the fat layer as the metal knives, but the skin is a bit more of a barrier. Its like cutting with safety scissors - the material that you want it to cut is easy to slice, but the skin that you don't want to damage offers enough resistance that you don't have to worry as much about slips.

End of the first degreasing
At the end of the day the hide is still heavy with grease, but its starting to look much more even and there are dry patches forming. I'm debating now when to cut it into the thong and what to do about the hair. I was kind of hoping that the seal would have been a little more decomposed and the hair would want to fall out on its own, but as it stands now, I'll either have to induce some decomposition to get the hair to fall out or shave it off.
The tools used so far
Shaving the hair seems like the safer, although more labour intensive, option - I'm worried that if the pelt starts to putrefy enough for the hair to fall out that I may not be able to stop the rot before it damages the skin. I also think that the neighbours (and Lori) have been through enough without me intentionally rotting sealskin in the backyard.

Photo Credits:
1, 5-7, 9-14: Tim Rast
2-4 & Video: Lori White
8: From Renouf and Bell 2008

16 comments:

  1. Fascinating, seriously fascinating. This whole set of posts with the seal pelt have been very, very interesting. Are you thinking about publishing this work? I really think you should - so many people would be interested in reading these ideas about the sinew vs baleen, or how much grease and fat are in the hide alone! We are so far removed from these activities yet we think we have it all figured out!
    Have you considered using a beamer for removing the hair? I`m sure you have. Is it too early at this point?

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  2. This has been an amazing few days and a huge learning curve processing our first seal skin and innards. Given we had so little notice we were pretty lucky Tim had the tools on hand that we did. It would have been nice to prepare our toolbox and house a little better but we've managed really well considering. If I could wish for any changes it would be colder weather, as we feel like we're racing the forecasted warm weather before the skin starts to putrify (and we start upsetting neighbours).
    I abandoned Tim yesterday and that wasn't very kind of me. It will take both of us, and perhaps the generous hands of a few friends, to remove the hair and cut the skin into a thong tomorrow.

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  3. Thanks Steve. Yeah, I guess I should find a way to publish this stuff in a format that is a little easier for folks to reference. If I would have had time to prepare for this in advance I might not be so surprised by every turn of events.

    I'm still struggling with the hair issue, but I'm leaning towards cutting the hide into thong with the hair on and seeing what happens. I really want this thing to dry when the sun and warm temperatures hit it and not start to stink. I think increasing the surface area by cutting it into a strip should help it dry out more quickly. If the hair doesn't fall out on its own and I decide that I want hairless thong I can always shave it later.

    There you go Steve - you made me say "I want hairless thong I can always shave it." That should drive the google traffic to the site through the roof.

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  4. Wow! A large greasy seal skin prepared with stone tools alone is a serious undertaking. I fleshed a raccoon hide once with a stone thumb scraper and thought that was a chore. And the results from the binding experiment are very enlightening.

    Also, I'd like to reiterate what Steve said above; publish, publish, publish!!! I know it is easier said than done, but I've learned a lot from your site. I'm sure others would enjoy and benefit from what you have to offer as well.

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  5. I know it is a long while away but I would be happy to have this written up in the PAO Archaeology Review for next year!

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  6. and oh yeah.....mmmmmm hairless thong.........

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  7. First it was Pamela Anderson, and now with the hairless thong... you're undermining our credibility here!!!

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  8. I tend to do that to everyone.

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  9. I intend to use the "Pamela Anderson" as my new measurement of almost everything.....

    It's interesting you settled on that big, tabular scraper. We happen to be talking scrapers at my blog today as well, and there are several accounts posts of using very large scrapers, hafted on to robust, baseball-bat sized handles, for use on moose and caribou hides. These were used with stone bits as recently as 1980 in NW British Columbia and of course continue to be used to this day.

    I was also intrigued by the use of seal blood as a glue...

    http://qmackie.wordpress.com/2010/04/02/caribou-metatarsal-hide-scraper/

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  10. Steve: Thanks - I can definitely write something up for the PAO Archaeology Review. I think that would be a good format and I like that its a little less formal and widely available:

    http://www.tcr.gov.nl.ca/tcr/publications/index.html#Newsletters

    qmackie: I read your blog post today and found it really interesting. I'm in a hide working frame of mind this week :) I guess I never really understood the importance of degreasing the hide before. The wide slate scrapers were ideal for pressing out the grease. By the end of today's work the little chert endscrapers became the right tool to use. The hide was dry enough that it started to get fuzzy on the inside. The slate scrapers would slide over that fuzz, but the sharper chert endscrapers would ball it up and cut it off.

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  11. This post reminds me of a question that's been rolling around in the back of my head for a few years. What sort of handle make a hide-scraping tool easier to use: the kind on an ulu or the kind on a parchmenter's knife?

    (A parchmenter's knife generally looks something like this: http://www.seniorlearn.org/bookclubs/readerguides/peregrines/parchmentier.html)

    Any thoughts?

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  12. I don't have any answers, but I could see the advantage of having a two handed handle for a hide scraping tool. It would give you more power and control and not overly tire out one arm. However, its makes a bigger, less portable tool. The ulu would have had many other jobs besides hideworking and the women using it would have spent a lot of the year travelling from camp to camp.

    I don't know much about the lives of parchmenters, but I'd guess that they had a more permanent workshop. They probably lived in a permanent village and had a workshop that they could keep all their tools hanging on a wall year round.

    It was interesting to see the parallels between ulus and lunellum. Very similar design for the same function and the names even sound alike.

    Thanks for the comment!

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  13. I found myself holding the ulu blade (not just the edge) flush to the skin more often than not, a position which I think would be hard to do with the two-handled parchmenter's scraping tool. The ulu also allowed me to easily switch back and forth between its use as a scraper and knife, depending on the thickness of the blubber.
    However, I imagine once the blubber was removed and the skin was at an even thickness I dare say the parchmenter's tool would work like a charm at thinning it out. Though, after all that time, sweat and labour I wouldn't have done it all for a piece of paper. I'd rather a pair of boots ;-)

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  14. Interesting.

    Tim: Yeah, parchmenters' workshops would have been in permanent buildings at the edges of town, downriver from everyone else, in the same neighbourhood as the other smelly craftspeople (tanners, butchers, etc). The lunellum would have been used specifically for scraping hides, and other tools would have been used for cutting.

    Lori: As far as I can recall, parchmenters would let the hides soak in a water-lime solution for a few days before even starting the scraping. That loosened the connections between the fat, hairs, and layers of skin, so that they peeled away relatively easily. They would then do a quick scrape to clean up what was left, then soak the hide again, before taking it out for the final stretching and scraping. I guess the lime did a lot of the work you guys did by hand... maybe they didn't need the flexibility with positioning?

    And hey, there's a reason books were rare in medieval Europe!

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  15. When I do animal skin i find there are different tools for different animals. Seal fat is easily cut off with an ulu by just making careful slicing action at about a fourty to fourty five degree angle. After i have rough fleshed the skin i place it in a frame and i cut off bits that i have missed. Thats the way that i learned to clean a seal skin.
    A good way to remove the hair from the hide is to put the seal skin into a small brook. Leave it there for a few days and then the hair will come right off. Thats how my grandfather would do it, if he was going to bark tan seal skin for boots. It was not uncommon either to shave the sealskin too for the bottom of the boots. they would leave the black outer skin on the hide and bits of fur to aid in traction
    You want to wash your sealskins too a few times in warm water to get as much grease as possible out of the hide. Because as long as you have grease you will have smell. I have heard that my ancestors(inuit) would use animal urine to wash the seal skin which helps to remove grease. I have to say i am thankful today for sawdust and borax. I also keep my sealskin out drying for a few months but in a somewhat shaded area or you will sunburn your sealskin. The prolonged drying process will help get rid of lots of grease. i always check it every once in a while wiping the excess grease off and giving it an extra scrape. You can never have your hides too clean.

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  16. Thanks Desmond! I really appreciate hearing about your experiences with sealskin. At this point, its been drying in the frame as a thong and the skin has become quite stiff and dark, although the hair especially seems to be holding on to a lot of grease. I test shaved a small section and the hair came off fairly easily. As you said, it had that black outer skin look to it. That is how I want the finished leather to look. The plan now is to shave it this weekend using an assortment of stone flakes. After the hair is off, I'm not sure whether I'll string it back in the frame or soak it in water a few times first. Probably soak it and then hang it under tension again. I have a couple projects that I'd like to use it on in the next month or so.

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