These photos are from A Nerd’s World: a Toronto Graphic and Design shop. They purchased a verascope and its glass photo slides from a Canadian estate sale, and the images turned out to have been taken by the French army in WWI.
A verascope works like a Viewmaster – each slide includes two photos side-by-side and it creates a three-dimensional image when you look through the viewer. To recreate the 3-D viewer online, the gallery made GIFs of the slides. It has quite a cool effect of making you feel like you are in WWI!
If the animations aren’t working on my site, you can click on each photo to view it from its original site.