Trench warfare in WWI was infamously brutal, but it also produced remarkably delicate works of art, called leaf drawings. According to the Public Domain Review, soldiers would pluck hardy oak and chestnut leaves, then draw on them with sharp objects like a pin or knife.
One artistic soldier was French Private Hippolyte Hodeu, and his grandson Thierry Dornberger still has the leaves with the names of Hodeu's daughters and the location of his personal muddy hell, Argonne.
As Dornberger relates, Hodeau "made the trenches and was gassed. Following the dull sound of a shell falling . . . he was wounded in the ear." Like many soldiers, Hodeau spent hours huddled in these muddy channels.
Many soldiers clung to life by killing time with arts and crafts. Leaves weren't the only material used – bullets and shell casings were formed into jewelry and candle holders. Leaves were light enough, though, to enclose in letters home, often with simple messages like a name or sentiments like "Your loving husband". And some were engraved with remarkably intricate drawings.
Due to the partial opacity of perforated leaves, the carvings are especially enchanting when lit from behind; sometimes they're called "feuilles de poilus", or "tree leaf lace".
Equally remarkable is the fact that these delicate mementos have survived for over a hundred years, or, have at least been photographed and digitized by organizations like Europeana Collections 1914-1918. Leaf drawings, like hope, seem ephemeral, but both have extraordinary staying power.