The gallery pages were showing the engravings in no particular order, and even though dates can be problematic, we do have approximate dates for most of the images, so I've now set it up to sort by date. That makes it much easier to browse the images with a mind to the way they change over time, and how particular features are concentrated in specific periods.

I think dates should be added back into the main index pages as a sort heading. They used to be in there, and I think they were removed for cosmetic reasons, but I'm going to think seriously about how to put them back without affecting the layout too much.