Scroll Length?

[Mortal Man]

For the record, it's "Fisher".

And I'm confident our methodology (which, truth be told, I devised) will be proven competent and its results verifiable.

Why would a world-renowned doctor of metrology need you to devise his measurement strategy?

[Mortal Man]

Spoken like an old Davis County boy.

As one whose house, growing up, was built in the middle of an apricot orchard south of the Farmington Cemetery, your very mention of apricots brings back bad memories of apricots rotting on the back lawn; apricots I had to rake up, scoop into a wheelbarrow with a shovel, and then dump into a rotting heap of apricot stink. It's only been in the past few years that I've been able to eat apricots again ...

Ah, the memories... We even built our own apricot dryer...

But speaking of apricot leather, I believe my mother made some batches whose thickness was in the neighborhood of 700 microns. Maybe your formula would work for apricot leather.

I'm certain that it would work wonderfully for apricot leather. Please have your mother send me some, even if it's only 167 microns.

ETA: And don't remind me of when my step-father tried to make apricot wine in the garage one year, and my curiosity got the better of me and I ventured to sample it ...

Don't try to blame this on your step-father Will. We all know what you were up to.

[Fifth Columnist]

Come to think of it, Will must do a lot to show that his thickness measurement is meaningful and reliable. First, he has to show that the thickness of 2000 year old papyrus can even be used to accurately assist in measuring the length of a scroll (beyond establishing its maximum length), especially since the established method does not use thickness at all. Second, he must show that the way he measured the JP papyri is accurate and reliable. This should be interesting.

Edited November 14, 2011 by Fifth Columnist

[Mortal Man]

It matters when it's as thick as Andrew needs it to be. If it's not that thick, then it doesn't matter. That's how it's "variable."

It's "variable" in the sense that what was once a grape is now a raisin.

[Uncertain]

I have been following this discussion with some interest. I did have a question I hope could be clarified. I am somewhat confused about how the papyri thickness is being used to validate/disprove a particular model. I read the Smith/MM paper but it was some time ago. If I understand correctly the "effective thickness" as calculated by Smith/MM is something like the average distance between successive windings. That is according to Smith/MM the effective thickness is probably not the actual thickness of the papyri. If I have two papyri of the same thickness the "effective thickness" could vary quite a bit depending on things like how tightly the papyri was wrapped and imperfections "bumps" etc that may be in the papyri. Is my understanding correct?

If indeed my understanding is correct I don't see why it is a big deal if the Smith/MM effective thickness is very different than the true thickness since the effective thickness by definition does not necessarily correspond to the actual thickness. Also since the effective thickness is an average this does not mean all windings are rigorously separated by the effective thickness some of them may be very tight and some them may be loose. How robust is the estimated effective thickness to outliers?

I initially thought the problem was most scrolls look like the example given by Will in post 51 in which the papyri is tightly wound. If indeed such scrolls are the norm than yes I would expect the effective thickness to be close to the true thickness. However MM posted an example of papyri in post 172 in which the papyri appeared to be very loosely rolled and there was considerable space between some of the windings. For such examples I have no problem believing the effective thickness will be very different and much larger than the actual thickness of the papyri.

If there are examples of papyri both loosely rolled and tightly rolled I don't see why the fact Smith/MM calculated effective thickness is different from the actually thickness corresponds to strong evidence the Smith/MM method is flawed. I also am somewhat confused by the "fruit rollup" picture given in post 118 that has been much discussed. The difference in "effective thickness" as calculated by Smith/MM and the measured thickness as calculated by Will is ~500 microns this is not a large space about the width of three average human hairs. It would not take many imperfections in the papyri to lead to a difference in average thickness between windings of three human hairs. As such the picture shown by MM in post 172 is not an accurate representation of his model having far to much space between windings. Perhaps I missed some sarcasm somewhere. Or perhaps I am just generally confused it would not be the first time .

Since I have not read Wills paper I have no opinion on who is right Will or Smith/MM. It just seemed in this thread much is being made of the thickness and I do not quite get how the thickness says much one way or another. Yes the thickness can be used as a first order sanity check it would be strange for example if the calculated effective thickness was less than the actual thickness. But I don't see how besides serving as a lower bound on the effective thickness much can be said one way or another using the actual thickness.

Best,

Uncertain

Edited November 14, 2011 by Uncertain

[Fifth Columnist]

Uncertain, everything you said sounds right to me. It appears that Will is trying to argue that the measured thickness is so far off from Smith/MM's effective thickness (measured thickness is not the same as effective thickness) that it calls into question their Smith/MM's winding measurements. Will has some winding measurements that were obtained in some mysterious fashion that he won't disclose that result in an effective thickness that is closer to the measured thickness. Will's methodology is novel and he has to do a lot to show that it is reliable.

Edited November 14, 2011 by Fifth Columnist

[Mortal Man]

Andrew, this is complete speculation, and you know it! You have no reason to suppose nor evidence to demonstrate that there is any decrease in papyrus thickness due to "gradual dessication process" or "other aging effects" or anything else. Your suggestion that any of these asserted "factors" would make any substantial difference is 100% speculation.

There is nothing speculative about it. This is well established fact. Papyrus is a plant with parenchyma cells comprised of mostly water. It contains natural gums in its cell sap which act as an adhesive for the two layers when they are pressed together. It is partially dried before use but retains sufficient moisture to remain pliable for rolling and to keep the layers adhered. As it ages, it becomes increasingly brittle due to further moisture loss and other factors. The dessication rate greatly accelerates when the scroll is unwound and exposed to the Kirtland sun in July. At this point, it becomes too brittle to roll back up, so you have to cut it into sections and glue it to backing paper. The accelerated moisture loss, due to exposure, also reduces the adhesion between the recto and verso layers, causing the top layer to flake off in regions where people keep poking it to point out Abraham's signature. At this point you have to put the thing under glass and mount it in a wooden frame. People sometimes do that with Autumn leaves when they get too thin and brittle to hold together.

[J Green]

Uncertain,

From my assessement of Will's measurements, we're looking at a thin, tightly-wound scroll. So while there are certainly several scenarios, as you point out, the data look to me as if they represent a scroll from Will's example photos--tightly wound with little-to-no dead space in between. The measurements also point to a gradual thinning as you reach the interior of the scroll. I'm still interested in how the grape/raisen/apricot leather analogy factors that data into the equation. The roll was tightly wound and sealed at the edges with bitumen. The thickness measurements show a gradual increase as you move toward the outer windings. Does this sound like a grape or a raisen?

Cheers

[Mortal Man]

You did tracings of three separate fragments, glued to three different sheets of backing paper of varying sizes. In order to return any kind of value for the edges, you would have to establish a baseline, a zero point, across each fragment. How did you go about establishing this baseline? How did you assure that the baseline was the same for each fragment?

We discuss this in the paper. There is no reason to make the baseline the same for each fragment, since they are analyzed independently. Furthermore, since the correlation function is independent of the amplitude of the edge input functions, the vertical location of the baseline makes no difference. There is a possible source of error in a potential misalignment of the baseline with the direction of roll. However, this error, is well below the reported digits of accuracy and hence is negligible.

[wenglund]

I have been following this discussion with some interest. I did have a question I hope could be clarified. I am somewhat confused about how the papyri thickness is being used to validate/disprove a particular model. I read the Smith/MM paper but it was some time ago. If I understand correctly the "effective thickness" as calculated by Smith/MM is something like the average distance between successive windings. That is according to Smith/MM the effective thickness is probably not the actual thickness of the papyri. If I have two papyri of the same thickness the "effective thickness" could vary quite a bit depending on things like how tightly the papyri was wrapped and imperfections "bumps" etc that may be in the papyri. Is my understanding correct?

If indeed my understanding is correct I don't see why it is a big deal if the Smith/MM effective thickness is very different than the true thickness since the effective thickness by definition does not necessarily correspond to the actual thickness. Also since the effective thickness is an average this does not mean all windings are rigorously separated by the effective thickness some of them may be very tight and some them may be loose. How robust is the estimated effective thickness to outliers?

I initially thought the problem was most scrolls look like the example given by Will in post 51 in which the papyri is tightly wound. If indeed such scrolls are the norm than yes I would expect the effective thickness to be close to the true thickness. However MM posted an example of papyri in post 172 in which the papyri appeared to be very loosely rolled and there was considerable space between some of the windings. For such examples I have no problem believing the effective thickness will be very different and much larger than the actual thickness of the papyri.

If there are examples of papyri both loosely rolled and tightly rolled I don't see why the fact Smith/MM calculated effective thickness is different from the actually thickness corresponds to strong evidence the Smith/MM method is flawed. I also am somewhat confused by the "fruit rollup" picture given in post 118 that has been much discussed. The difference in "effective thickness" as calculated by Smith/MM and the measured thickness as calculated by Will is ~500 microns this is not a large space about the width of three average human hairs. It would not take many imperfections in the papyri to lead to a difference in average thickness between windings of three human hairs. As such the picture shown by MM in post 172 is not an accurate representation of his model having far to much space between windings. Perhaps I missed some sarcasm somewhere. Or perhaps I am just generally confused it would not be the first time .

Since I have not read Wills paper I have no opinion on who is right Will or Smith/MM. It just seemed in this thread much is being made of the thickness and I do not quite get how the thickness says much one way or another. Yes the thickness can be used as a first order sanity check it would be strange for example if the calculated effective thickness was less than the actual thickness. But I don't see how besides serving as a lower bound on the effective thickness much can be said one way or another using the actual thickness.

Best,Uncertain

Are you suggesting that no amount of space between the windings would seem problematic to you?

If not, then how much space would raise concerns? Would it be double the thickness of the papyri, triple, quadruple?

Thanks, -Wade Englund-

Edited November 15, 2011 by wenglund

[Mortal Man]

Will, I think the onus is on you to demonstrate that deterioration and other effects haven't adversely affected your thickness measurements:

http://cool.conserva...12/bp12-10.html

Here is a description of papyrus deterioration in general.

http://books.google....oration&f=false

This is a nice illustration of papyrus deterioration.

http://www.lib.umich...ystem#sec-rolls

The JS Papyri have obviously deteriorated. I think you are making a huge assumption that the deterioration has no effect on the thickness.

Nice links FC.

Will, do you think this papyrus is as thick today as it was originally?

[Bill Hamblin]

It's "variable" in the sense that what was once a grape is now a raisin.

This is a silly argument. The problem with the argument is that in the ancient manufacture of papyri most of the water was already squeezed and dried out of the papyrus before writing occurred. I've seen the process done. Certainly some desiccation could occur with papyri over 2000 years. But I very much doubt that papyri could have a 50-60% shrinkage over time, which is what would be required to collate the Chris/Andrew estimate of an effective thickness of 600 microns with the measured thickness of under 200.

Note, most importantly, if the required 50%+ shrinkage in the thickness of the papyri over 2000+ years required by the Chris/Andrew theory had in fact occurred, we would see that shrinkage reflected in warping of the length and width, not just the reduction of the thickness. It would be most apparent by warping of the vignettes and texts. While there is plenty of damage and flaking, I don't see any warpage to the length and width that one would expect if the papyri had shrunk the requisite 50%+ necessary to accommodate the Chris/Andrew claimed original 600 microns thickness with the actual measured thickness of under 200 microns.

The fact that the Chris/Andrew claims cannot be reconciled with the empirically measured thickness of the extant JS papyri should lead an objective observer to conclude that something is wrong with the theory, rather than claiming that something is wrong with the data.

[Mortal Man]

It causes the thickness to be increased on account of the fact that the layers of papyrus begin to separate!

Another gem for my collection.

I have made no "huge assumption". Quite to the contrary, I documented the observed damage, as well as its effect on the measurements we were making. An analysis of that effect is what leads us to conclude both that the scroll of Hor was tightly wound from an inner core, and that the inner windings would have been likely to measure even thinner than did JSP-X, which averaged ~150 microns.

You're not going to make any progress with JSP-X until you measure its windings.

[Bill Hamblin]

Nice links FC.

Will, do you think this papyrus is as thick today as it was originally?

I suspect you are confusing damage with thickness. What you see in this papyrus is damage and decomposition, not thinning.

How, precisely do you think this shrinkage of ancient papyri would have occurred?

[Bill Hamblin]

Another gem for my collection.

You're not going to make any progress with JSP-X until you measure its windings.

So you don't believe that if multi-ply papyrus fibers start to separate the the distance between the upper fibers and lower fibers would not increase?

[Mortal Man]

You evidently still don't get it. In Will's case, the thickness of the papyri is determined by actually measuring the thickness of the papyri. The measurements that Will professionally obtained, are shown via the cited example to be consistent with other papyri of the period.

Whereas, in MM's case, the thickness of the papyri is a by-product of his winding measurements, which conflict significantly with actual professional measurements of the papyri.

Here is why MM's formula is potentially problematic: with the formula that I and perhaps Will has been using, any inaccuracies in measuring the winding lengths will have but a one-to-one impact directly on a single variable--i.e. the winding lengths in general, and the circumference of the outermost winding in particular. Whereas, with MM's formula, inaccuracies in measuring the winding lengths will have an exponential impact not only on the length of the scroll, but also on the thickness of the scroll. And, with the kind of inexact measuring technique at the heart of their calculations (based on a hand-drawn outline), the exponential factor can wreck havoc with the numbers, potentially distorting them to the point that the results appear absurd in the face of reality--as evinced by how radically different MM's thickness measurement ended up in comparison with what was professionally measured.

Wade, this is complete nonsense.

[Bill Hamblin]

I suspect that MM/Andrew is aware that a grape turns into a raisin by evaporation of water. Once the water has largely evaporated, the raisin doesn't keep shrinking, does it?

I believe that one of the reasons papyri survive so well in the Egyptian desert, but don't survive in wet climates is because water permits bacterial decomposition. Papyri in desert climates (like Egypt and Qumran) survive in part because they are perpetually dry, and bacteria can't cause decomposition. That's why we find lots of Greek papyri in Egypt, but almost none in Greek itself, and why we find it in the deserts of Egypt far more than in the delta.

[Mortal Man]

Papyrus thickness is not a value anyone has ever attempted to determine. The way I conceived of doing it will constitute the first time anyone has developed a methodology for measuring the thickness of papyrus in a preserved status. John Gee is submitting to several Egyptological journals a short article describing the innovative methodology.

First of all it's unethical to submit the same article to multiple journals. In all the journals I've worked with, you confirm when you submit the article that you haven't submitted it anywhere else.

Secondly, if the Toronto scroll is made of papyrus then Gee has mistakenly measured half winding lengths and this will prove to be a great embarrassment.

Thirdly, if he is attempting to marry Hoffmann's formula with the physical thickness of papyrus then this will prove to be a great embarrassment.

[Mortal Man]

Imagine a papyri roll of a certain circumference.

a- Is the thickness of the original papyri a variable in how long of a scroll you could wind into that circumference?

Yes

b- Is the tightness of the original winding a variable in how long of a scroll could be wound into that circumference?

Yes

[Mortal Man]

Tightness and thickness are certainly variables in how much you can wind anything. However, Egyptologists have determined that winding lengths account for both of those variables as well as all other variables such as deterioration so that only winding lengths are used to estimate the length of a papyrus roll.

If Will wants to rely on thickness to show the length of a roll, then he will need to do the heavy lifting to show that it can be reliably used this way. He is the one who needs to do all the tests you challenged MM and Chris to perform (test it on existing papyrus, account for deterioration from oxidation, age, humidity, etc., etc.). Will is the one who is breaking new ground with his method. MM and Chris used the already established and proven method.

Well said.

It's like trying to predict how long it will take a nascar to complete 20 laps on the track at top speed.

The Standard Method: Measure its velocity for 8 laps and then divide the total distance by this velocity.

William's Method: Measure the fuel consumption of a Ford Model T for 3 laps on a dirtbike course; assume this rate of consumption for the nascar; make wild claims about engine efficiency; proclaim that there is no such thing as aerodynamic drag; assert that the car slows to a crawl after 8 laps because the driver looks tired; finally, juggle these numbers as necessary to fit your predetermined conclusion.

[Bill Hamblin]

Yes Yes

At last a clear answer.

Does your formula account for the possibility that the inner wrappings might be more tightly wrapped that the outer ones you actually measured?

Did you measure the thickness of the JS papyri?

[wenglund]

I suspect that part of the reason for the warping and uneven spacing in the papyri exhibit above is due to the relatively large circumference of the inner winding, which allows some amount of buckling and give, and this as opposed to the relatively small circumference and nominal amount of warping in the image Will has posted. (Of interest, back in 2009, in this post, Will explained that the Greenfield papyrus pictured above, "was wound using an umbilicus, but the umbilicus had been removed.")

Also, the Greenfield Papyrus (pictured above) measures 123 ft in length (37.4904 m) and 18.5 in. in width, as compared with the Joseph Smith papyri ~20 ft (6m) if Will is to be believed, or ~4 ft. if Andrew and Chris are to be believed. The added length would like manifest a greater amount of dessication than a scroll 1/5th its length--and this assuming much if any effect of dessication.

Even still, if you look at the thickness of the papyrus in relation to the average space in between the windings, at best the space may be double the thickness (I am being real generous here), but hardly quadruple the space posited by the Andrew/Cook calculations.

I am currently searching for various measurements of the Greenfield papyrus (circumference or diameter when rolled up, thickness of the papyrus, etc.) that might also put things into perspective. If anyone here has access to this information, please let me know.

Thanks, -Wade Englund-

[Bill Hamblin]

There is also, of course, the possibility that the rolling of the outer wraps of the papyrus might have been crooked, which I suspect would skew the measurements if measured from a straight baseline.

[William Schryver]

I am currently searching for various measurements of the Greenfield papyrus (circumference or diameter when rolled up, thickness of the papyrus, etc.) that might also put things into perspective. If anyone here has access to this information, please let me know.

Thanks, -Wade Englund-

I can't reply to other posts on this thread for the time being--FHE and whatnot. But I will tell you, Wade, that you will not find any measurements for Papyrus Greenfield. I corresponded extensively with a curator at the British Museum on that and other questions. There are no measurements, other than length, for Papyrus Greenfield.

[William Schryver]

There is also, of course, the possibility that the rolling of the outer wraps of the papyrus might have been crooked, which I suspect would skew the measurements if measured from a straight baseline.

You're only scratching the surface of the problems with the Cook/Smith winding length measurement methodology. Good news, though, I have learned today that there is an initial critique of Cook/Smith that will be published in the near future.