Research has been going well. My Bodleian card gives me access to the superb Sackler Library and I already have answers to most of the questions I had lined up a couple of weeks ago, giving me a pretty good idea of what the landscape and coastlines of the island of Salamis and mainland Attica could have looked like from the south-east, the angle I think I have now settled on for my bird's-eye view of the battle.
I still have to check whether the barleyfields on Salamis and the mainland would have been stubble or plough at the time of the battle, and several additional questions have, not surprisingly, emerged. One thing that could significantly affect the view from the air is the accommodation arrangements for the 100,000+ extra inhabitants of the island (regular population 2-3,000) and the gear and supplies needed to support the Greek fleet. There must have been an extensive spread of tents and other temporary structures along the shoreline between the permanent settlements.
I took it for granted that the battlefield itself, the stretch of water fought over in the straits, would not have changed. However, I now know that the present-day water level has been shown conclusively to be approximately 5ft higher than it was in 480BC. At the scale I shall be using this will hardly have a visible effect on the shorelines, but it will mean drawing in a small island (shown in some maps of the battle, not in others, and hardly ever mentioned) that is not now visible. This makes the water between the island of Hagios Georgios and the mainland even more of a chokepoint and very likely to have marked the northern perimeter of the Greek postion. Overall, of course, it means the straits were an even tighter fit than they would have been today (if cleared of modern container ports and bulk carriers) for the battling fleets.
A session in the Bodleian Map Room equipped me with copies of the contour maps I was looking for; the best available seem to be German Army 1941! A 1987 British Admiralty map, soundings in fathoms, will also come in useful for sketching out the 5th century shoreline. And I will be tracing my base map from a very clear drawing of exactly the area I want, just missing that extra island, found in War at Sea: Modern Theory and Ancient Practice by one Reginald Custance. This is a very useful and, I think, unique overview study of several sea battles. However, I have to be a little cautious with Custance's interpretations. The book was published in 1919 so "Modern" means World War I, and it took me a while to notice that the scale was in cables and nautical miles! Reading this, a lucky find on the shelves where I was looking for something else, helped me to arrive for myself at an crucial general insight: it is very important not to overlay present-day conceptions of strategy and strategic thinking, planning, staffwork etc on the military culture of a world in which abstract thought and language were hardly even in their infancy. Herodotus, our main source, was the first known historian, "the father of history" and he wrote about the Persian War decades after it was over. And the western world (Sun Tzu got there sooner) had to wait decades more for the first thinking and writing on the art and theory of war.
But now, I have most of the information I think I need with some fair visual references, a stack of large sheets of squared paper with tracing paper for overlays, a bundle of pencils and coloured pens, a gallon of correcting fluid and a shaking hand. The moment of truth cannot be avoided for much longer.... Because I have not been as disciplined as I might have been (OK, I've been having a lot of fun), I have also begun collecting information for the battlescene art brief which I'll be doing next and finding out a lot of interesting stuff about triremes and 5th Century seafighting. The volume of material about the reconstruction and operation of the Hellenic Navy's trireme "Olympias" has been a particularly happy hunting ground.