And the process continues. I still do not like the Glasgow point, and all I can say really is that it doesn’t feel right. As so after playing with it for a while I decided to opt for an overtly plano-convex approach with my next attempt. The rationale behind this was to make the process simple. Rough out the shape by attacking one surface only. This would also create a platform all around the preform. I could then use this platform to punch out large flakes making the plano-convex cross section and giving the piece the characteristic look.
For this second point I selected another blank from the Camp Coffee bottle, this one from the ‘& Chicory’ section. In theory the plano-convex approach would leave on the lettering.
In practice, it didn’t. I like this point, although it is difficult to explain exactly why it looks and feels more correct. It is approximating a lens shaped profile, and I was able to be more confident in how I worked this piece. It may simply be that in plan this piece looks similar to the museum examples I have seen. All I can say is that I am pleased with it. The ‘&’ is a useful landmark to show how much material has been removed.
Whilst it didn’t work out exactly as expected, I enjoyed the process of working through an idea. The emerging goal seems to be to get four points from the four blanks produced from the Patterson’s Coffee bottle. That would be a satisfying result 🙂
After quartering the Camp Coffee bottle yesterday I roughed out the first Kimberley Point. This morning I finished it (I think).
The ASGO are useful landmarks for recognising how much material has been lost.
However, I am not quite sure if I like it. It is not quite plano-convex, and not quite lens shaped. This is partly an artefact of design as I was aiming to keep on some of the lettering. However it also doesn’t have the consistent deep invasive removals that have characterised the museum points I have seen. It does have some, especially forming the tip, but not enough to give the overall impression that the museum pieces do. Perhaps it is not finished. Perhaps I need to handle and play with it for a while to know. I am pleased with the serrated edges for which I used a flattened end of a number eight wire. I will report the results of my deliberations…soonish.
Yesterday we had a knapping session in the department lab. The above is an old Patterson’s Camp Coffee bottle base recovered from Chorlton Ees, and as can be seen, the glass is thick, uneven and with bubbles. Because of its square form I decided to try quartering it following the method described by Stanley Porteus (1931: 111-112) recorded after observing an aboriginal knapper producing blanks for Kimberley Points. The first step is to use a number eight wire to remove the base, and in this I was unsuccessful. The thickness of the base (~9mm) made it too strong, however during the process one of the side panels fractured nicely. I shifted to a small hard hammer and worked along the second longitudinal edge of of the fractured panel and I was able to remove it cleanly. Perhaps the subject of another post, but there were clear sonic signals as to how thick the glass was at each point, and I responded to that iteratively with the amount of ‘umf’ I applied.
This gave me confidence and I continued working along the remaining longitudinal edges. Voila, bottle quartered into four usable blanks using a small hammerstone.
I have tried this process before with a modern Bombay Sapphire bottle and it didn’t work. That I believe is because of the thickness of the glass being used. Like most modern glass bottles the Bombay Sapphire is well engineered presumably to optimise strength and minimise materials used, therefore weight. Consequently the Bombay Sapphire fractured unpredictably. The quality of the glass is everything here. Whilst the uneven thickness and bubbles on old glass present their own set of problems, the actual thickness provides some internal cohesion that makes it relatively forgiving to manipulation and modification. This suggests to me that Kimberley Points were ‘of their time’, in that the uneven thickness of early glass gave it qualities akin to a stone flake, and these were recognised as such by aboriginals. This similarity has diminished over time as glass has become more engineered. Aboriginals continued knapping materials such as Pyrex and window glass into the 1980s (Akerman pers. com.), and the methods would seem to have adapted as materials developed. Within this relatively short historical period a really interesting dialogue between human skilled practice and material development has played out. This was in tandem with an aboriginal recognition of the new qualities such as size, colour and transparency that could be marshalled into the traditional production process. In my own modest way I am, following in this tradition, and currently working on a ‘Glasgow’ Kimberley Point, which I am sure will be the subject of a post soon.
Porteus, S.D. 1931. The psychology of a primitive people. London. Butler and Tanner Ltd.
This is a link to a short video of Karl Lee pressure flaking glass . It is of interest to me because it illustrates how he uses his knee “like a vice” to remove the flake. The large piece of glass was modern, and probably a table top. This is the end result.
Today has been miserable in Manchester, an ideal day for being sat behind a desk, sorting out all those jobs that need doing. I found myself in the backyard, in the rain. I have been inspired since my visit to the museum earlier in the week, and think I am getting it. Consequently, I took three points made previously and reworked them, or refined them to bring them more in line with the museum examples.
I know you shouldn’t have favourites, but it’s the middle one. Then the one on the right and then the one on the far left. I actually learned the most from working on the one on the far left, and then was able to apply that learning to the other two. Essentially my edge control is getting good. This is allowing me to get flatter points, and in turn serrate the margins more subtly.
This is one of the museum examples with a broken tip, angled to show the degree of retouch. You can see how the flaking really penetrates up to half way in creating a ridge or spine.
This is my version. Shape and size and margins are all good. The needle like tip is needle like, the area to improve is fully invasive retouch. It needs to penetrate further in. I therefore need to take a leaf out of Nick Overton’s book and sort that out on my first pass, then bingo!
This morning I paid another visit to the Manchester Museum and Gareth Frier was kind enough to dig out their Kimberley Points collection for me. My aim was to compare and contrast two of my own points with the museum originals. The two points in question are produced from the same piece of period glass bottle (see here and here) and are headed for Eleanor Casella’s teaching collection. Long story short: one of my points is a good replication, the other less so.
The above right is the ‘less so’. The point on the left is the original and as can be seen, it is much more refined in its retouch. They are keeping their retoucher much sharper, as it states in the texts, and it is interesting to see what that actually means in practice. Consequently, the original sits flatter on the paper in spite of its twisted longitudinal profile, and I now think that it is this flatness that allows more detailed edge serrations. I went in thinking it was edge angle that would be different, but it is flatness, which leads to a reduced edge angle and ultimately thinner margins that can be serrated. I have left my version with Eleanor as I said I would drop it off today, but I would like to continue flaking in order to flatten it, if she wants me to.
I am pleased with this second one. To all intents and purposes it fits the Kimberley Point criteria. The point on the left is the original and it has been made from a thick (at least 7mm) piece of glass and completely flaked on both surfaces. Mine on the other hand is made from the side panel of a glass bottle and has some original ventral surface left. This is true for almost all the other pieces, though usually to a lesser degree. I have also left some original dorsal surface to keep the lettering because I like it, and other examples discussed had this. I am pleased to say that this piece would be at home in the box with all the other originals.
I was more cautious with this one and it turned out longer. I tried to stick to my method, ventral first, then dorsal, then the point, however the angle of the edge face made me improvise a bit. I am pleased with the needle like point, and am going to arrange to go back into the Manchester Museum to compare and contrast. I think the key difference between mine and the actual points may be thickness and edge angle. Let’s see.
The next post will be about home made pressure flaking tools, as we have been innovating in our twice weekly knapping get-togethers.