Edgar Barclay and Herbert Thomas

This is a moody painting of Stonehenge by Edgar Barclay, dating from around 1895.  It's not widely known that this artist played a role in the attempts to identify the sources of the bluestones.  Around 1906 he had in his possession assorted chips of "bluestone" collected from Stonehenge during his many visits as a painter.  He showed them to HH Thomas and asked him where they might have come from.  HHT was at that time working on the Geological Survey of West Wales, and he had some suspicions that the source of the rock chips might have been in the eastern part of the Preseli Hills.  He did not, at that time, know the local geology well enough to say anything definitive.  But a seed was sown in his mind, and in Edgar Barclay's little book called "Stonehenge", published in 1908, HHT recorded his "tentative conclusions" as to provenance.

As we all know,  this led to a closer and closer interest in the origins of the bluestones -- and although Thomas was preoccupied with other matters as a professional geologist in the period 1908 - 1920 (and although everybody had to live through the trauma of WW1) he had a working hypothesis in his mind which he was able to test when he really homed in on the bluestone enigma for two or three years of intensive work.  And that, as we all know, led to the famous paper in The Antiquaries' Journal in 1923.