The speakers in the video are Alice Insley (Curator British Art 1730 - 1850) and Rachel Scott (Paintings Conservator)
Alice: This painting is called A Portrait of a Man and it shows a gentleman seated in an interior, and he's sitting next to a table with writing material and a letter on it. Arthur Devis was an 18th Century painter, and he was a specialist in conversation pieces. That was a kind of painting that became very popular at that time, and shows groups of people quite informally.
Rachel: The painting was chosen for a conservation treatment because it had a really dark yellowed varnish, and a lot of discoloured retouchings. In fact the left side was covered in a quite a crude thick overpaint, in colours that didn't match the original paint.
When I started to look at the picture in the studio, there was a canvas join down the left side. This had actually been trimmed from the bottom of the painting, turned on its side and joined to the main canvas. It dawned on me that it was cut down from a larger portrait. The figure feels quite large within his surrounding space.
Alice: And knowing that Devis specialised in group portraits probably made it a kind of educated guess as well.
Rachel: The next steps were really to see if we could track down the other half, and I did a lot of research but I couldn't find anything that fitted. So I knew the next step would be to visit The Courtauld Institute, that has a wonderful picture library. I met Alice in the studio and by total coincidence, you said "I happened to be visiting The Courtauld this afternoon so I'll take a look for you." But I don't think, I don't think either of us held out much hope at all.
Alice: I started looking out for anything that might look like a matching table or a kind of matching fireplace or even the matching floorboards. I didn't really have much luck, and then I did just happen to alight on this picture that I suddenly thought, this looks like it might be a match.
This picture shows a woman seated, again, in an interior setting and there's what I thought could be the fireplace on the right hand side, and then the table also has some writing instruments on it. I think I took a picture on my phone and sent it straight by email that afternoon.
Rachel: I used Photoshop to line up the floorboards with the two images side by side and the floorboards lined up perfectly and that I think was really the moment when we realised that was confirmation that it was definitely the pair. I've never encountered anything like this before so it was very exciting.
Alice: We don't know for certain why the picture was divided in two, but the best guess is probably that it was to make two pictures around the one, and to be able to sell it on as two. It would be amazing if we could reunite them. I think it would help us see what the original intention of the painting was, and of the artist. It'd just be wonderful to be able to find out a bit more about what happened to the painting through comparison.
Rachel: It's just strange to think it's out there somewhere and the owner doesn't know that the other half is here at Tate.