In the late 1860s, artist, "amateur" zoologist, and maker Eugen von Ransonnet-Villez built a personal submersible so he could draw the otherworldly scenes he observed under the sea. (Did he actually see that skull on the ocean floor? Or is it, as my brother Bob suggests, a memento mori?) From the Public Domain Review:
Measuring three feet high by two and half wide and deep, this submersible, of sheet iron and inch-thick glass, had the user's legs sticking out of the bottom so that he could propel himself along the seabed at a depth of five meters or so. It was weighed down by cannonballs, and with air pumped in, the diving bell allowed him to descend for sessions of up to three hours. Jovanovic-Kruspel et al in 2017 point out that "The sight of a dead dog floating on the surface nearby was a very welcome sight to Ransonnet as it proved to him that there were no sharks to be feared."
Undisturbed, and drawing with a soft pencil on greenish-coloured, varnished paper, Ransonnet could use a tin box to send up to the surface his finished pictures, which he later painted over in oils: the first depictions of the seascape executed by an artist under the sea.