This reminds me of a long time ago when I was traveling by train in Europe. It was hot and stuffy despite the windows being open with muggy air blasting in. We were standing in the halls as it was better than in the rooms. Then someone barfed - luckily they made it to the window. Later I went for a walk along the train. The next carriage back was strangely empty - until I noticed the barf splatter on the inside wall of the hall. You could see the silhouette of where people had been standing.