May 2015

This is an index and summary of the things I've talked about over the last month. Links for multi-post subjects go to the first post (even if it's before this month), you can follow the internal navigation links from there.



"The Sea Thy Mistress" Elizabeth Bear - third book in the Edda of Burdens series. New.

Total: 1


All Seeing.

And I Must Scream ...

Look to the Stars.

Looking for the Greener Grass.

Symbols of Power.

Total: 5


The Photon - In Our Time episode about light & photons.

Total: 1


"The Ark Tablet: How the Life of an Assyriologist Could be Transformed by a Single Tablet with Sixty Lines of Writing" Irving Finkel - the fourth talk in the BSS Study Day on cuneiform.

"Egyptian Fortifications in Canaan" Rupert Chapman - talk at the May EEG meeting.

"The Royal Game of Ur: From Ancient Grave to Modern Rebirth" Irving Finkel - the third part of the BSS Study Day on cuneiform.

Total: 3



Cleopatra: A Timewatch Guide - a rather substandard programme about how our ideas of Cleopatra have changed over the years.

Total: 1


Egypt Holiday 2014: Seti I Temple at Abydos.

Egypt Holiday 2014: Ramesses II Temple at Abydos.

Egypt Holiday 2014: Dendara Temple.

Total: 3

Tags: Admin

The last talk in the Bloomsbury Summer School's Cuneiform Study Day was about the ark tablet that Irving Finkel has recently published a book about. There was also a TV documentary about the discovery of the tablet, and the building of a boat using the information in the tablet as a starting point (which I've written about before). The talk was mostly unconcerned with the TV programme, but about halfway through Finkel did go on a digression about the awfulness of it (as he saw it) - the "turning it into 'good' TV" process made it shallow and theatrical in all sorts of ways he didn't like. He did think the boat was cool, tho!

Finkel started off by giving us some context for Flood Stories in cuneiform texts (which is exactly what I complained the TV programme didn't do). George Smith in 1852 was the first person to read a cuneiform tablet containing a version of the Ark Story. This was the first time it was shown that a Biblical story pre-dated the Bible. The impact of this in society at the time was huge (much larger than it would be today), as it's such a fundamental Old Testament story. There are close & specific links between the story that Smith read and the Biblical version, too. One of these is the releasing of the two birds to see if there is any land yet. However the boat as described in that text is cubical, so those who were particularly upset said that showed it was all a coincidence. The tablet that Smith read is part of the Epic of Gilgamesh, and is actually one of the more recent cuneiform texts with a Flood Story. Since Smith's discovery other (older) versions have been found. Although details differ, including the protagonist, they all share a common point that the gods had decided that the creation of humanity had been a mistake. The gods thus cause a flood to wipe them away, but one man is saved by one god warning him.

The new tablet that Finkel has translated & published dates to around 1800BC. It was initially brought to the British Museum along with various other bits & pieces by a man who'd inherited it from his father (who'd picked up these things on various trips). Finkel thought it was a letter at first glance, but then when he read the first lines it was clear that it was a Babylonian Flood Story and it didn't match the ones he'd seen before. Which was very exciting, but sadly the chap who owned it took it away again and it was a while before Finkel had the chance to properly study it.

This version of the story includes a "How To" manual for building the ark. Unusually it describes a boat that is round - shaped like a coracle. Coracles are normally pretty small scale, but this one is much bigger. Finkel made the point that it didn't need to go anywhere (coracles are normally propelled by oars, so it might be difficult to move a larger one) - for the occupants to survive the flood it only needed to float. The numbers and instructions in the text are surprisingly specific - not like mythological numbers generally are. If you calculate how much of the materials you would need to make a boat of that design the figures come out within 1% of those in the text. And the instructions match up well with those in a book published in the 1930s (AD) talking about coracle building in the more modern Middle East. So this is effectively the story being interrupted for an (accurate) info-dump about boat building. Finkel pointed out that this would've been of interest to the audience for the story, particularly if it was told orally (as it probably was) - there would be many fishermen and other river-goers who might want to know just how big this big boat was and so on. (It made me think of things like Tom Clancy's novels where the story gets interrupted for a loving description of exactly what sort of gun is being used).

After his digression about the TV programme Finkel talked about his interest in the broader picture into which this tablet fits. Primarily - how did this ancient Mesopotamian legend end up retold in the Jewish Bible? Clearly the Exile of the Jews in Babylon must have something to do with it. Judea is invaded twice by Nebuchadnezzar, and this is documented in both the Old Testament and in the bureaucratic records of the Babylonian Empire. The texts corroborate each other to a pretty high degree - for instance there are people named in the text of the Hebrew Bible who are also mentioned in Babylonian documents. The second invasion of Judea is when Jerusalem was sacked and the bulk of the Jews were forcibly marched to Babylon. Finkel talked a bit here about what it must've been like for the Jews - his analogy was that in terms of culture shock it must've been much like it was for the rural Eastern European Jews who emigrated to New York in the 1930s.

The Book of Daniel talks about the young nobles of the Judeans being instructed in the language and literature of the Babylonians during the exile. This was a policy on the part of the Babylonians intended to indoctrinate the Judean elite with Babylonian culture, so that they would be less likely to rebel and instead be assimilated. Evidence from the Bablyonian side of the education of the Judeans includes a tablet which lists the Aramaic alphabet in cuneiform signs. The cross-cultural mixing went both ways - written around this time is a Babylonian tablet musing about monotheism and postulating that all the other gods are manifestations of Marduk. I.e. that Adad is "Marduk of the Rain" and so on.

At the time one of the ways students learnt to read & write was copying out set texts. From student tablets that have been found archaeologists have some idea of the school curriculum of the time that the Judeans were in Babylon. The stories they would've been copying included not only the Flood Story, but also one with a baby discovered in bulrushes and other legends of early rulers who lived unfeasibly long lives. And these all have parallels that end up in the Hebrew Bible.

This was a good talk to end the day on, and answered several of the things I was curious about after the TV programme. I intend at some point to read his book about the tablet, too. Overall this was a very interesting study day. Finkel is a very good speaker - my write-ups of his talks are sadly a rather dry rendition of the actual performance.

Temple Facade
Temple of Hathor at Dendara

We visited Dendara after Abydos as it's on the way back to Luxor. The temple here is dedicated to Hathor and is much more recent than the two at Abydos - it's Ptolemaic and Roman era, although built on the site of older temples. One of the well known reliefs on the temple is of Cleopatra VII (ie the famous one) and her son Caesarion. We actually saw more of the surroundings of the temple than the inside - going up on the roof, under the floor and around the outside. My photos from this visit are, as always, up on flickr - click here for the full set, or on any photo to go to its flickr page.

plan of Dendara Temple Complex
Plan of Dendara Temple Complex
Made by wikipedia user Sinuhe20

Key: A. Roman Kiosk; B. Domitian and Trajan Gate; C. Roman Birth House; D. Coptic Church; E. Ptolemaic Birth House; F. Sanatorium; G. Sacred Lake; H. Temple of Isis; I. Well; J. Sanctuary; K. Hypostyle Hall; L. Vestibule; M. East Gate

We entered the temple complex from the north, going through the Domitian & Trajan gate, and pretty much bypassed the buildings to the right. We first paused at the facade before passing through into the vestibule. My main impression of this space is that there's a lot of blue - it's the colour that seems to've survived best on the reliefs. The columns are striking as well - not the more usual papyrus shaped tops, instead they have Hathor's head near the top with the column above her carved to look like a sistrum (or rattle). The ceiling is still intact and in this room it's decorated with astronomical reliefs - when we visited 5 years ago it was in the process of being cleaned so there was a lot of scaffolding in the way. I'd meant to come back towards the end of the visit and take more photos but ran out of time, sadly.

Temple FacadeInside the Vestibule
The Facade (left) and Inside the Vestibule (right)

Instead of continuing further into the temple we made our way up to the roof. We went up via the stairs on the right hand side which follow a (square) spiral path up to the roof. They were used by priests during festivals and the walls are carved with priests walking in procession. When lit by flickering torches it must've looked out of the corner of your eye as if they were walking alongside you. Once up on the roof we walked through a Ptolemaic era kiosk with blank cartouches - the turnover of Pharaohs during this period was at times brisk enough that the artists never quite got to the point of writing in the name.

Stairs to the RoofOsiris Rooms on Roof
Stairs to the Roof (left), Relief in the Osiris Rooms

The roof isn't flat, even on the bits that don't have structures on - it depends on the height of the room underneath. We stopped next to the central section and Medhat pointed out just how big the stones here are, and the difficulty the Egyptians must've had in transporting them and raising them with the technology they had available. At the front of the roof there's a couple of rooms dedicated to Osiris - Hathor being associated with the Osiris myths (she nurses Horus), and also because Dendara is another place that Osiris is supposed to be buried. The first of those rooms is where the famous zodiac ceiling comes from (now in the Louvre) - it's been replaced by a plaster replica, painted black to match the rest of the ceiling. Which is a shame, as it given it's a replica anyway it would've been interesting to see it painted in colours like the original once was - of course the state of knowledge when the original was removed possibly means that wasn't an option. The inner room is decorated with scenes from the legend of Horus's conception and birth - which occurs after his father Osiris's death. His mother Isis had succeeded in resurrecting Osiris for long enough to impregnate her, and this is depicted in the reliefs as a mummy lying on a bed with an erect penis. The falcon hovering over this is Isis being impregnated. I seem, inexplicably, to have no photos of these - instead I paid more attention to other motifs in those rooms.

View of the Eastern Gate from the RoofCrypt
View From the Roof (left), Crypt (right)

After looking at the view from the roof we headed back down the other stairs to the main part of the temple. We then had the opportunity to visit one of the crypts underneath the temple. These were storage spaces for the temple valuables, and the entrances were hidden. As they were functional and secret spaces I wasn't really expecting them to be decorated - but of course that's not the way the ancient Egyptians thought! The one we looked in was covered in very fine decoration - it's quite narrow so I sadly didn't get any good photos of the sweep of the scenes.

Relief of Cleopatra VII and CaesarionTemple of Isis
Relief of Cleopatra (left), Reliefs in Temple of Isis (right)

Next we headed around the outside of the temple to look at the Cleopatra relief on the back wall, and while we were there one of the guardians opened up the Temple of Isis so we could have a look inside. This small building dates from the Roman period, still decorated with Egyptian motifs (as their religion last for a few hundred years after they became part of the Roman Empire) in the clumsy style I associate with Ptolemaic and/or Roman reliefs. We then walked back towards the front of the temple looking at the other reliefs on the outside of the western wall and at the sacred lake. The "lake" is completely dry now, and Dylan told me that even when the temple was in operation it would've fluctuated a lot with the seasons. Just before the annual flood it might've been no more than a sacred puddle.

Sacred Lake
Sacred Lake

A slightly odd visit, as I said at the beginning we saw more of the outside than the inside. Perhaps another time we'll look around more at the interior reliefs.

The Sea Thy Mistress is the third book in Elizabeth Bear's The Edda of Burdens series, following on from the end of both of the preceding books (All the Windwracked Stars (post) and By the Mountain Bound (post)). It's pretty much impossible to talk about this book without some spoilers for the other two, so be warned there are spoilers ahead even for this one.

Both the previous books are stories about the end of the world, whether it be by a bang (BtMB) or a long drawn out whimper (AtWS). The Sea Thy Mistress is about a new beginning, and the tension comes from the vulnerability of the newborn world. At the end of All the Windwracked Stars Muire willing took up the role of Bearer of Burdens and brought life back to the world. But the Lady Heythe has ridden out of the first ending of the world into this new beginning. The world changed while she wasn't there but she only aims to finish the job she started in By the Mountain Bound.

This story is also Cathoair's story. With Strifbjorn's soul but not Strifbjorn's memories he's an apt central character for this part of the trilogy. He (and the world) are at root the same as the previous man (world) but he (and the world) is also distinct and his (its) own individual self (world). And I hadn't thought about it till writing this, but I think there's a similar resonance for the world & the protagonist of each of the previous books. Muire & the world didn't quietly give up & die in All the Windwracked Stars, instead they kept on going and even appearing to live despite the despair and/or dying that was concealed inside. I find it harder to articulate how the Wolf and the world match in By the Mountain Bound, but I still feel they do - something about being broken by someone using their very nature against them.

This story might take place a few decades after the end of All the Windwracked Stars, but it's still a direct sequel. Cathoair hasn't got over the traumatic events of the end that story. Muire is still gone, Astrid is still dead by his hand. He's an immortal now - a new angel for a new world, and as such has a purpose and is alive. But he's not really alive, more going through the motions. That starts to change when he becomes responsible for bringing up his son - Muire was pregnant by Cathoair when she made her sacrifice and the babe has been born and sent back to the living world (the Bearer of Burdens is presumably not a role that meshes well with bringing up even an immortal child).

And it is into this new life that Heythe walks. Of course the reader knows more than the protagonists do about Heythe - except the Wolf, but the Wolf is not trusted by Cathoair. And so Heythe has the cracks and flaws in Cathoair & the world that she needs to drive her wedges in and try to prise it all apart again. But this book is not a tragedy, and this new world is not as fragile as it first seems - there's genuine hope at the end that the wounds of the last world are healed.

This has been one of my favourite of Bear's series that I've read. I like what she's done with Norse mythology, and I like the world & the people she's created to inhabit it. I left it a bit long to write up this book, so I think I've forgotten some of the things I wanted to say about it, which is a shame. But I'm sure I'll re-read it some day :)

On Sunday Rupert Chapman came to the Essex Egyptology Group to talk to us about his work on Egyptian fortifications in Canaan. He started by telling us about the different sorts of Egyptian fortification that exist, which have been categorised into four types by an author called Morris. The first two types are never found in the Levant; these are fortresses that control entry points into Egypt proper (for instance at Tell Haboua) and fortress towns such as Kuban in Nubia. The third type are migdol forts - migdol is a Hebrew word that means "tower" and the distinctive feature of these structures is a gate flanked by two towers. An example of this in Egypt is the entrance to Ramesses III's temple at Medinet Habu. Chapman also compared them to much more modern structures - the early 20th Century AD Tegart Forts built by the British in Palestine (although those do not necessarily have two towers). The fourth type of Egyptian fortification, and the other one found in the Levant, is called an "administrative HQ" by Morris.

Chapman moved on to give us some context for the time period he was going to talk about. Contact between the Levant and Egypt occurs throughout Egyptian history (and probably before!). Chapman told us he'd been present during an excavation in the Levant that discovered the name of Narmer on one of the objects found - so evidence of contact immediately after the unification of Egypt. This early contact is based on trade, and the evidence suggests that the economies of the Levant and Egypt were intertwined - during the Intermediate Periods in Egypt the economy of the Levant tended to collapse as one of their big trading partners wasn't trading as much. However despite this early and consistent contact there is no evidence for Egyptian fortifications in the Levant until quite late on in Egyptian history. During Horemheb's reign at the beginning of the 19th Dynasty a lot of new bases appear. There is evidence for permanent settlement of Egyptian people in the Levant in the 19th & 20th Dynasties. This includes bodies in cemeteries who were laid out as if they had been mummified (although if there was any attempt to mummify them it wasn't that successful). They had been wrapped in Egyptian quality linen and were buried with Egyptian goods, and sometimes in improvised ceramic coffins. Interestingly there is also evidence of Aegean peoples in the Levant at this time - they were mercenaries in the Egyptian army. There were also Aegean mercenaries in the Hittite armies at this point, and so at the Battle of Kadesh there were Aegeans on both sides.

The next part of the talk, which was probably the bulk of it, focused on a selection of the sites in Canaan where Egyptian fortifications are found. The first of these are the string of so-called "Governor's Residences" along the coast road leading from Egypt to the Levant. Petrie excavated them & named them thinking of the British Empire Residencies he was familiar with, but Chapman thinks it's more plausible that this structures are police posts. So rather than an important official each fort would be used by a small garrison who guarded that section of the important trade route. They weren't as fortified as you might think - whilst they could withstand a local riot or a Bedouin raid they wouldn't be much use against an army. So they're more about keeping traders safe than occupying foreign territory.

Chapman then moved on to discuss one of the 10th Century BC (so c. Third Intermediate Period) "palaces" at Megiddo. He says that the floor plan of this building is clearly more analogous to an Egyptian building than a local Levantine one. The gates in particular show features typical of Egyptian entrances and not local ones. The walls are built using Phoenician building techniques but have the very deep foundations that are characteristic of Egyptian fortification walls. Chapman's theory is that the "palace" was built by Shoshenq I who founded Dynasty 22. As corroborating evidence there was a fragment of Shoshenq I's victory stela found at Megiddo, however this is not a theory that all the experts share.

The site at Beth Shan a bit south of the Sea of Galilee has been occupied since the Neolithic and several levels of the archaeology are Egyptian. The buildings have Egyptian type layouts and construction, and some of the more substantial ones even have Egyptian inscriptions and decoration. There is also a lot of pottery of Egyptian designs found in these strata - not just the sort of thing that might be imported, but also the everyday type of thing that would be used once or a few times and then disposed of. The Egyptian presence here runs from the 18th Dynasty through to the 20th Dynasty and the site is the "administrative HQ" type - in one of the levels they have identified an admin building with a grain silo, probably used for ration distribution.

The last of the sites Chapman talked about was Tell es-Sa'idiyeh in Jordan and unlike the other sites the excavations there haven't been published yet. The site is in east Jordan, and controls access to a fordable place on the river Jordan as well as one of the major trade routes running eastwards from there. There are two periods of definite Egyptian occupation of the site, the later of these dates to the 19th-20th Dynasties. The site is not all that well fortified - it wouldn't've held off more than raiders - and so again it falls into the "administrative HQ" category of fortifications. This particular spot is a good place for an Egyptian Royal Estate: it's in one of the few places in Jordan where it's wet enough to produce high quality linen, it is on the olive oil and wine trade routes and so controls them and it's a good grain growing region. Chapman thinks they have identified the commisariat (food and drink supply point) for the city in a building originally designated the "Western Palace". Inside this (Egyptian style) building there are bread ovens and a grain silo. Just outside it is a pool, attached to the water supply for the city in which were found several storage jars - which would've been placed there to keep their contents cool. The water supply itself is an Egyptian feature - the spring just outside the city walls is linked to the city via a covered walkway & staircase of a design often found in Egyptian fortifications in Nubia. In the Levant these are also found only in Egyptian sites and not local ones.

The end of the Egyptian period of occupation is interesting as the city appears to've been destroyed although not by enemies. First there are signs that it becomes a bit run down, doors are blocked up and buildings get a bit unmaintained. Then the whole city is burnt down - all the valuables removed, leaving just things like the large pottery storage jars that were in the pool at the commisariat (too big and too cheap to be worth the effort to move). Chapman believes this is a sign of an orderly retreat on the part of the occupants, destroying the city after they left so that it couldn't be used against them if they were to return to reconquer the area.

The last part of Chapman's talk was rather more speculative - a couple of his thoughts & theories about the sites he talked about and some things further afield. For instance - during the Mycenean period in Greece, which is contemporaneous with the Egyptian occupation of these sites there is a sudden appearance of forts that are very similar in design to these Egyptian ones. There's no hint that there is any Egyptian occupation, just buildings of that sort of design (including the concealed & protected water systems). Chapman speculates that this has something to do with the Aegean mercenaries in the Egyptian army at this time - when they go home they take the Egyptian army techniques with them. Either they work for the local rulers or become the local rulers, and build forts the way they've learnt how to do.

Keeping with the mercenaries in the Egyptian army Chapman also talked about what may've happened after the Egyptians pulled out of Canaan at the end of the 20th Dynasty. As he'd discussed in the context of Tell es-Sa'idiyeh this seems to've been an orderly retreat - valuables cleared and later destruction of the forts by the previous occupants. He speculates that perhaps the period where the fort gets run down before it is destroyed is actually after the main Egyptian army pulled out and the mercenaries (or some of them) might've stayed on occupying the fort and taking advantage of the power vacuum left by the retreat of the Egyptians. He thinks this might possibly be the kernel of truth behind the Phillistines in the biblical stories of David and Saul.

Tell es-Sa'idiyeh doesn't get abandoned forever after the destruction of the 20th Dynasty fortification. At first there is a small village on the site, and then a new town which appears to've been planned and laid out in one go rather than growing over time from the village. There is evidence that it is again making linen, and although the temple they've found is in a Canaanite architectural style there are indications that it was for the worship of Min. So Chapman speculates that this is again a royal estate as it was back in the 20th Dynasty, although he didn't say if he thought this was a Canaanite estate with imported linen makers, or a Egyptian one. After this town was destroyed by the Assyrians the rest of the history of the site through until the Roman period is as a sort of grain depot where grain from the surrounding area is collected together and stored. Chapman thinks this is another sort of royal estate (not Egyptian this time). Interestingly, it's known that Anthony gives Cleopatra an estate in Jordan during his period in power there. Chapman thinks it's not outside the bounds of possibility that this was Tell es-Sa'idiyeh, and perhaps Cleopatra even requested that one because it was associated with Egypt in the past (I'm not sure I buy this latter part, there's so much time passed and dynasties come & gone between then and Cleopatra that I'm not sure there would be records of which estates had been where or whose).

This was a talk of two parts, really - the earlier discussion of the archaeology was quite dry but in the last part where Chapman began to speculate a bit more broadly the subject came more to life.

Inside the Temple
Inside the Temple

As well as completing his father's much larger & more famous temple at Abydos Ramesses II also built a temple of his own. It's much smaller, and there is less of it still standing, but there was still enough for an interesting visit. In fact, we could've spent quite a lot longer there - I managed to only see half the inside of it! My photos are, as always, on flickr - click here for the full set or click on any image (except the plan of the temple which isn't mine) to see it larger on flickr.

plan of the Ramesses II Temple at Abydos
Plan of the Ramesses II Temple at Abydos, from wikimedia

The only plans I found with a license that meant I could use them were labelled in German but I think it's clear enough what's what (at least of the bits I'll talk about) :) We approached the temple from the south east (left hand side of the plan), walking across the very short bit of sand that separates the Seti I temple from this one. The modern ground level is much higher than the ancient one, and the remains of the walls are truncated at head height or thereabouts. So there's a slightly odd effect as you approach it of suddenly tripping over a buried temple.

Medhat Pointing Out the ReliefsBattle of Kadesh Scenes
Medhat pointing out the calendar reliefs (left), Battle of Kadesh scene (right)

We walked round the outside first to look at the the reliefs there, starting on the left (on the plan) walking round the back and down the right hand side before coming round to the front entrance. The first wall is effectively an instruction set for operation of the temple - it's a calendar of festivals and the offerings required. The next two walls are scenes depicting the Battle of Kadesh - this is Ramesses favourite theme for temple decoration and it's returned to again and again on the places he orders to be built. This battle took place in 1274BC between the forces of the Egyptian Empire (lead by Ramesses II) and those of the Hittite Empire (the dominant Mesopotamian culture of the time). It happened at a place called Kadesh, which is near the modern Syria-Lebanon border and is in a strategically important place between the two ancient empires. The outcome is now thought to've been a draw but both sides claim in their own records that they won. It was to be an integral part of Ramesses II's propaganda narrative during his reign - during the battle he'd been lured away from the main force of the Egyptian army and he says in inscriptions that when he was surrounded by his enemies he called upon the god Amun and then singlehandedly defeated his foes and returned triumphantly to the rest of the army. A good story to use to portray oneself as favoured by the gods and the rightful ruler of Egypt, but unlikely to be the objective truth ;)

Battle of Kadesh ScenesBattle of Kadesh Scenes
Battle of Kadesh Scenes
Battle of Kadesh Scenes
Battle of Kadesh scenes

We spent quite a lot of time looking at those reliefs as even in their damaged state there's a lot of detail to be seen. The soldiers, whether Egyptian or those of the enemy aren't just a homogeneous mass - they have different faces. There are bodies in the river - a particularly horrifying fate for an Egyptian as drowned people didn't make it to the afterlife. Scenes of armies marching as well as scenes of battle. Scenes of Egytians taking captives, and counting the slain (via cutting off their right hands and counting those).

At the door of the temple we paused for a bit while it was being unlocked, and Medhat pointed out something in the hieroglyphs at the gate that I wouldn't've spotted myself. There are traces of green in the depressions of some of the large ones - these are marks left by the copper inlay that was once in the hieroglyph. That must've been quite a sight to see when new - not just the doors themselves gleaming (being made of gilded wood) but also the hieroglyphs around the doorway catching the light.


Inside we started to look around the courtyard and here I got completely distracted by a piece of graffiti on the wall so didn't move on much past the courtyard. I asked Dylan about it and he said it was probably made by a priest at some time while the temple was in operation. Clearly it had been made by someone who knew something of both the techniques and styles of temple reliefs. It was blocked out in red ink to get the layout right, a standing figure surrounded by 2 (or 3?) kneeling figures adoring him. And he'd started to carve the scene - the main figure and some of the hieroglyphs were done, but not all. Quite good work, and it must've taken some time to get as far as he did - generally I think of graffiti as scribbled words, but this was of a rather different calibre.

Reliefs Inside the TempleReliefs Inside the Temple
Pharaoh clutching the rekhet bird (left), Thoth and Pharaoh (right)

As I said, I didn't look much round the rest of the interior - something for another visit :) I did have time to take a handful of photos, tho. My impressions are mostly of how much paint there was left, despite the large scale damage to the walls the bits that remained were in pretty good nick.

Inside the Temple
Reliefs Inside the Temple

The episode on In Our Time about photons was summed up near the end by all the experts agreeing with an Einstein quote that if you think you understand what a photon is then you're deluding yourself! So that makes it a trifle daunting to write up the episode but is reassuring in that the reason the subject feels slippery & hard to grasp is because it is :) The three experts who joined Melvyn Bragg in discussing photons were Frank Close (University of Oxford), Wendy Flavell (University of Manchester) and Susan Cartwright (University of Sheffield).

Close opened the discussion by giving a summary of the 19th Century view of light. The key idea at this time was that light was a part of the electromagnetic spectrum. The electromagnetic spectrum is the name given to waves formed electromagnetically - an electrical field builds up, which generates a magnetic field, the electrical field fades away as the magnetic field builds up, and a new electrical field builds up as the magnetic field fades away. These waves can have any frequency, and scientists showed the light was a part of this spectrum (i.e. that this is what light is). The existence of non-visible frequencies was predicted after this.

This didn't, however, explain all the known observations of light. Cartwright discussed the "black body problem": as you heat something up it starts to emit light, first red, then yellow and so on up to the bluer wavelengths. Planck figured out that this sequence can be explained if you assume that the light comes in little packets of energy (quanta), and that the amount of energy in each packet is determined by the frequency of the electromagnetic light wave. I don't think I'd heard of the "black body problem" before, but I was aware of the existence of Planck's constant - which is part of this theory.

At the time Planck was thinking about this problem it was assumed that the quanta were a property of the heated object and not of light itself - after all it was "known" that light was a wave and waves don't come in discrete particles. Flavell explained that Einstein suggested that light might need to be thought of as a particle as well, but most people thought that was ludicrous. It wasn't until after experiments done by Compton on interference patterns, which produced results that could only be caused by light being made up of particles, that it became accepted that photons are both waves and particles.

Having brought us up to speed on the history behind the theory of light's paradoxical existence as both a wave & a particle the experts moved on to discuss more of the properties of photons. Photons are massless, consisting only of energy. This is why they travel at "the speed of light" - that's the speed of a massless particle, anything with mass must travel slower. Photons are bosons one of the two broad classes of particles - the other being fermions. The classes are distinguished by how many can exist in the same quantum state at the same time. There can only be one fermion in each quantum state (and this is why we don't fall through matter), but there can be more than one boson in each quantum state. Photons are also the mechanism by which the electromagnetic force is transferred around between objects.

The wave/particle duality of photons is one of the pairs of things that can't be measured at the same time. This is the Heisenberg Uncertainty Principle, which I had heard of before but hadn't realised applied to more than position/speed of particles. The experiments that demonstrate this practically are some of the weirder experimental data I've heard of, a proper demonstration of the counter-intuitive nature of quantum physics. If you look at light passing through a diffraction grate, then you see interference patterns - this is light acting as a wave. However, if you measure it at the level of single photons passing through, then you have "forced" the light to act like a particle by counting them and there are no interference patterns. And bizarrely if you measure like this and then delete the data the patterns reappear!?

My write-up of this has definitely not done the subject justice - physics is my weakest subject by far, especially quantum physics. Still interesting to learn a bit about, tho :)