An old Magic Lantern slide from a lecture on Stonehenge that I bought for a couple of quid off eBay.
(click for much larger)
It shows the section behind stone 56 from Gowland's excavations, as illustrated in his report:
It came without any history. Is it some amateur's interpretation of the excavation, hand drawn because he couldn't copy the printed illustration, or could it be from the original lectures that Gowland gave outlining his work before the report went to press? The differences in the labelling suggest to me that it isn't a copy from the report, but is an original sketch by an expert. An expert on the excavation but not in preparing slides as the labels are half hidden by the border. But then I am biased.