This is a vintage illustration depicting a scientific demonstration. The central focus is a glass bottle with a narrow neck and a wider base. Inside the bottle, a peeled hard-boiled egg is shown partially descending through the neck. The egg appears to be squeezed and distorted as it passes through the opening. Around the egg within the bottle, there's a swirling pattern of lines suggesting a vortex or pressure effect. To the left and right of the bottle are fragments of broken eggshells, indicating the egg was initially whole. The background is a dense, grainy texture, likely representing a shaded or darkened environment. Below the image, there's a caption that reads: "Fig. 43.—Hard boiled egg, divested of its shell, passing through the neck of a glass bottle, under the influence of atmospheric pressure."