One of the most useful exercises to do when trying to understand the construction of an early codex is to build a model. With early codices, it is always the case that we don’t have all the information that we need to accomplish this with total accuracy, but the process of making a model helps bring to light some of the unanswered questions. I’ve mentioned on the Variant Readings blog some of the models I’ve made in the last few years–for instance, Nag Hammadi Codex III (TM 107743) and Codex VI (TM 107746).
In connection with an article I recently wrote, I made a model of the papyrus codex containing Paul’s epistles in Greek split between the Chester Beatty Library and the University of Michigan (a.k.a. P46, TM 61855). It is another single-quire codex. It’s the largest (that is to say, the thickest) codex that I have tried to make. Nag Hammadi Codex VI had 20 bifolia, Codex III had 40 bifolia, and P46 is estimated to have had 52 bifolia. Only 43 bifolia survive, but the pages of the codex were numbered, so the reconstruction of the size of the quire is reasonable (though not certain, as I discuss in the aforementioned article).
Over the next few posts, I’ll describe some the issues I encountered in making the model. The feature item I’ll discuss is the size of the bifolia.
When a thick single quire is folded in half, the innermost sheets protrude. Ancient bookmakers solved this problem by making the outermost bifolia of the quire broader than those in the center of the quire. In the case of the better preserved Nag Hammadi codices, this change in size can be clearly documented with leaf by leaf measurements. P46 is a bit more damaged, and so we must do some estimation to determine the original dimensions of its bifolia. The breadth of the central bifolium of P46 is reasonably well preserved, with just a bit of wear on the edges. The original breadth was likely about 26.8 cm. The outermost bifolia of the codex have not survived, and the outermost bifolia of the codex that do survive are quite damaged. In his thorough PhD dissertation on P46, Edgar Battad Ebojo has estimated that the outermost bifolium of the quire likely measured about 32 cm (based on the measurements of the largest surviving bifolia). So, between the innermost and outermost bifolium, there was likely a difference of just about 5 cm, as illustrated below.
With a total of 52 bifolia, each bifolium should be about 1 mm less wide than the previous one from outside to inside. So I decreased the breadth of each sheet by 1 mm as I cut them. The resulting stack looked like this:
Even with this adjustment, however, I found that the central bifolia still protruded a bit when the quire was folded.
I had similar results with my model of Nag Hammadi Codex III:
I suspect that these large single-quire codices in antiquity probably did have this uneven fore-edge. I am aware of only one good photograph of an ancient intact single-quire codex that clearly shows the fore-edge; this is the Berlin Akhmimic Proverbs codex (TM 107968). The codex is of course damaged, but it does appear that the central bifolia protrude quite noticeably (and this in spite of the fact that the outermost bifolium is about 4 cm broader than the central bifolium). (Side note: I’m unsure of the ultimate source of this photo; I found it in Sharpe’s chapter, but I don’t know where he got it. I would love to have an image developed from the original negatives, as there are many details that cannot be made out in this scan.):
It is sometimes suggested that the fore-edge of single-quire codices could have been trimmed after binding to achieve a flat endge (e.g. in James Robinson’s writings on the Nag Hammadi codices). This is in theory possible, but I wonder how, in practical terms, such trimming would have been carried out in antiquity (I’m genuinely curious; suggestions are welcome!). It seems like it would be a tricky procedure with ancient cutting tools. For now, my assumption is that the bifolia of single-quire codices were cut to size before folding.
In the next post, I’ll discuss the binding of P46 and the use of stays in single-quire codices.