How does a Barbed Harpoon Work?

The oldest style of harpoon in the world is the barbed harpoon. A harpoon is a spear-like device with a detachable head tied to a line. When the barbed harpoon head is embedded in the flesh of the prey animal, the barbs grip the tissue and the hunter has a secure line attached to it. Its similar to how a fish hook catches a fish, but its used on larger fish and sea mammals. Sometimes the hunter holds the other end of the line and sometimes the line is attached to a float that drags behind the prey, identifying its location, preventing it from escaping and exhausting it.

In Newfoundland and Labrador, the Maritime Archaic Indians used barbed harpoons similar to the one labelled above. They most likely used it for seal hunting. This is my best guess for how the harpoon might have looked. If you visit the Maritime Archaic exhibit at The Rooms, you'll see this label next to the Maritime Archaic Indian foreshafts like the one in this reproduction: "Whalebone foreshafts were used for sea mammal hunting. Exactly how they functioned has puzzled archaeologists for decades." That's still totally true - take all the reproductions that you see on these pages with a grain of salt. I wasn't there.

However, in my kitchen, I did finally get all of the components of the ballistic gel seal working the way they should; skin, fat, and meat. For the meat layer, I tried denser ballistics gel alone, but it wouldn't hold the harpoon head securely enough when I tried to pull it out. Next I tried lacing the dense gel with sinew threads, but the barbs just grabbed them and pulled them out like spaghetti on a fork. Finally, Lori gave me some cheese cloth, which I cut into circles and suspended at various depths in the gelatin. The loose weave was punctured by the antler harpoon head, but there was enough form to the cloth that it held together and gripped the harpoon head when I tried to pull it out. I don't think I quite have a realistic muscle consistency, but by increasing the density of the gel and adding more and more cheesecloth layers I know I'll be able to have a lot of control over the accuracy of the model.

In the tests with the barbed harpoon, we got lucky with two different views of the barbs in action. On the first attempt, my bad aim and a wobbly gelatin tower caused the harpoon to go astray and not penetrate the "meat" layer. However, the barbs snagged securely on the rawhide skin layer. In the second photo below you can even see the path the harpoon head took through the gel before being pulled back up to snag on the skin.

On the next test, the harpoon penetrated deep into the "meat" layer and through 3 of the 4 layers of cheesecloth. The "meat" had enough substance to grip the barbs of the harpoon on the way out. It held firmly enough to prove the concept and get these photos, but in actual experiments I think I'll use a denser gelatin (in this version I used 1 packet of knox gelatin for every 100ml of water) and more layers of cheesecloth.

Its interesting to note that when the harpoon head grabbed on the skin layer it used the barb closest to the line hole and when it grabbed in the "meat" it used the barb closest to the tip. There is a lot of variability in Maritime Archaic harpoon heads of this style, with anywhere from 1 to 4 barbs along one edge or both edges. That would be another interesting thing to examine in these experiments - the differences in the number and arrangement of barbs on a barbed point.

I'm loving this project - if testing the ballistics gel is this much fun, I can't wait to start actually testing the harpoons!

Photo Captions:
First & Second: Tim Rast
Third - Eighth: Lori White

Photo Captions:
First: Labelled Maritime Archaic Barbed Harpoon
Second: Label next to Maritime Archaic foreshafts at The Rooms
Third: Ballistics Gel Seal test using barbed harpoon
Fourth: Barbed harpoon head grabbing the skin layer
Fifth: You can see the trackway of the harpoon preserved in the gel!
Sixth: The barbs grabbed the cheesecloth in the meat layer!
Seventh: Its the distal barb that is doing all the work.
Eighth: You can really see the cheesecloth gripping from this angle.

What are the parts of a Toggling Harpoon?

Here's a quick look at the parts of a Dorset Palaeoeskimo toggling harpoon and some of the tests to find a good ballistics gel seal to do harpoon experiments with.


This style of harpoon is used to attach a line to a seal. The hunter gets close enough to the seal to jab it with the harpoon, the harpoon head detaches and toggles beneath the skin of the seal. The hole where the line attaches to a toggling harpoon is near the middle of the harpoon head, so when the seal tries to escape, the harpoon head toggles, or turns sideways. A toggled harpoon head is bigger than the hole it made going in and is firmly embedded in the hunters prey. The line is used to haul the seal out of the water so that the hunter can finish it off.

That toggling action is one of the things I'm trying to illustrate with the ballistics gel seal. This particular video still doesn't show the harpoon head toggling, but I did learn a lot from it. One thing it illustrates is that the skin and fat layer of the ballistics gel seal work very well. They offer the right amount of resistance and are good approximations of the outer layers of a seal. The Dorset Palaeoeskimo harpoon heads from Newfoundland that I have modelled this harpoon on have a single line hole, and I believe that the line must have been secured to the harpoon head with a big knot of sinew on one side. On the test in the video, the sinew knot bulged out of the smooth contour of the harpoon head. It created a raised bump a couple millimetres high, but it was enough to snag on the rawhide skin. The resistance from that tiny snag was enough that the harpoon was bound up and the whalebone foreshaft broke. I learned two things. First, if I'm going to use a sinew knot to secure the line, it needs to be flush with the surface of the harpoon head and secondly, the forces involved in the experiment are great enough that things break when they go wrong. Which is also good, because examining how things break is very useful information when studying broken and discarded tools in the archaeological record.

After the foreshaft broke, I pushed the harpoon head down into the gel manually and it did toggle for me when I pulled on the line. In the photo below, you can see the gel tube suspended from the toggled harpoon head and line. The gel is still a little opaque to see everything that's going on, but you can make out a few interesting details. In the overhead shot, you can see the hole that the endblade made and the shadow of the harpoon head lying beneath the rawhide skin. In the inset shot you can see the endblade, which detached when the harpoon head toggled. It marks the depth that the toggling occurred, although the harpoon head itself squished up through the ballistics gel "fat" layer and is actually snagged just below the skin. You can see the rubbery rawhide skin flexing upward under the tension.

Photo Credits:
First, Second: Tim Rast
Video: Lori White
Third, Fourth Photo: Lori White

Photo Credits:
First: Labelled parts of a Middle Dorset Harpoon Reproduction, Elfshot 2009
Second: Showing the detached harpoon head
Third: Detail of video frame showing the sinew knot in the harpoon head line hole when it grabbed the raw hide.
Video: Testing the ballistics gel. The foreshaft breaks when the harpoon head snags on a knot in the sinew
Fourth: The harpoon head toggling in the Ballistics gel.

Fair and Ballistic Gel Seal Anticipation Builds!

I needed to pick up some shelves and other display items for my craft fair booth yesterday and had a chance to briefly stop by the Fine Craft and Design Fair to check out the show and my booth space. This was my first time visiting the fair in the Arts and Culture Centre and I'm really excited now about joining the fair this week. The place was hopping! At 10 days, the fair is twice as long as it has ever been and the layout and auxiliary events create a big festive atmosphere. The Craft Fair fits into the space so well, that its almost like a new mall dedicated to craft has sprung up in the middle of St. John's. The show is closed Monday and Tuesday to switch over booths and re-opens on Wednesday November 11th at 4:00pm with a new set of craft producers.

But of course, the inside of my head still looks something like this:

(You can make make your own Wordle at Wordle.Net!)

I spent more time working on the ballistics gel seal model. The current version is the 3 layer pop bottle seal. There is a rawhide skin layer, the smooshy fat layer and the sinew laced meat layer. I cut the top end off the two litre pop bottle and used it for a funnel so that I could cut a relatively small hole in the bottom to fill it from. I stretched a wet rawhide skin from a soaked chew toy for dogs over the top, like a drum skin. I flipped it over and filled it up upside down. The initial gelatin pour seeped through the wet rawhide. It was kind of messy, but in the end it helped keep the rawhide rubbery and more skin like when the gelatin set. I used 5 packs of Knox gelatin for 700 ml of water for the fat layer. I did that twice, so 10 packs for 1400 ml of water would be the same thing. For the meat layer I used 7 packs for 700 ml of water and poured it in 3 stages. Between each stage I let it gel slightly and sprinkled soaked sinew strips into the mix. That gives me about 4 inches of "fat" and 2 inches of "meat".

That's as far as I've got. I'll know later today if they work and what changes need to be made.

Photo Credits:
Top, Tim Rast
Second, Wordle.Net
Third & Fourth, Tim Rast

Photo Captions:
Top, Earrings ready for the 2009 Fine Craft and Design Fair, St. John's
Second, Wordle created using the text from the past week's blog posts
Third, Filling the ballistic gel seal. If you expand the photo you can see the sinew in the "meat" layer.
Fourth, Ready to test!

Harpoon Foreshafts and Gelatin Seals

Between the leftover Halloween candy and visions of giant gummy seals I hardly slept at all last night. I've been thinking a lot more about the ballistic gel seal idea.

I think that in order to properly test both barbed and toggling harpoons the gel seal would have to have three layers. Skin, blubber, and meat. I think rawhide would work for the skin layer, and two layers of gel could serve as the blubber and meat layers. The meat layer would be a dense ballistic gel and the blubber layer would be a gel made with more water, so it would be a little squishier. If you aren't squeamish, you can see the layers that make up a seal here: culture camp how to butcher a seal demo.

I've been using Knox Gelatine (its spelled that way on the box) to make the ballistics gel. To make edible gelatin, the recipe is one packet of Knox's for 500 ml of water. I'm using about 700 ml of water and in the first batch I used 2 packets of Knox. This made jello. All it was missing was the sugar and the floating peas and chunks of ham. I remelted the gelatin by floating the tupperware in a sink full of hot water and mixed in a third pack of Knox. The 3 pack-700ml gelatin block is the one I used in these photos. It held together a little better although it still failed (the third picture in the triptych below). It might make an ok fat layer, but I think its still softer than any real animal fat. I'm melting it down again and I'll add a fourth pack. My guess now is that 4 packs of gelatin will make an alright fat layer and that I'll need at least 5 or 6 packs to the same volume of water to make a dense enough muscle layer.

One thing that this avenue of thinking has illustrated for me is the functional difference between the long foreshaft on the barbed harpoon and the short foreshaft on the toggling harpoon. They start to make sense if you think of a seal in three layers, with skin and fat near the surface and meat somewhere deep inside. The toggling harpoon head works in the fat near the skin while the barbed harpoon needs to grip the denser muscle tissue deep inside the animal. The different lengths of the foreshafts would deliver the harpoon heads to the appropriate depths inside the seal.

The harpoon reproductions on the left are two different cultures, and all of the tools made by the Palaeoeskimos were smaller than the Maritime Archaic equivelant, so its kind of like comparing apples and oranges. However, the Maritime Archaic Indians also made toggling harpoons, and the foreshafts for those are much shorter than the foreshafts on the barbed points. One recovered at Port au Choix with the Maritime Archaic toggling harpoon head still attached was only 18 cm long. Out of context, it could have passed for a large Palaeoeskimo foreshaft (the foreshaft in my Palaeoeskimo reproduction is 12 cm long). The Maritime Archaic made both barbed and toggling harpoon heads and they made both long and short foreshafts, which makes sense when you consider where each of these kinds of harpoon heads would work best inside the body of the marine mammals they were hunting.

Maybe an experiment built around foreshaft lengths would be a good excuse for stabbing blocks of ballistic gel with harpoons. I'm thinking about other tests involving barbed versus toggling harpoons and stone endblades versus self-bladed harpoon heads. Thank you everyone for commenting on the last post - keep the ideas coming.

Photo Credits:
First, Third, Fifth: Lori White
Second, Fourth: Tim Rast

Photo Captions:
First, Stabbing a gelatin block with a barbed harpoon head
Second, Knox' gelatin and the container of gel
Third, Stabbing rawhide and gel with a Dorset harpoon. The glass is there to give the harpoon head room to toggle, but it didn't happen.
Fourth, Maritime Archaic barbed harpoon, top, and Dorset Palaeoeskimo toggling harpoon, below
Fifth, still stabbing gelatin