I imagine amusement park safety was lax in the 19th century, but this is ridiculous. An 1891 issue of Scientific American showcased this invention by a one Monsieur Carron of Grenoble, France. In short, Carron had invented an amusement ride that involved 15 patrons falling almost 1,000 feet inside a 30-foot-long bullet, which then would land inside a champagne-flute-shaped, 180-foot-deep well. Explains the article:
Mr. Charles Carron, an engineer at Grenoble, has analytically studied the conditions in which the punctuation of the water by such a shell would be effected, and the reactions that the passengers would have to support. The conclusions of this study show that there is nothing, either theoretically or practically, opposed to its construction and to its operation in falls reaching three hundred meters. The accompanying figures give the general aspect of such a shell capable of accommodating fifteen passengers falling from a height of 300 meters [...] The passengers would be securely seated in arm chairs that exactly followed the contours of their body.
In theory, built-in mattresses and the champagne-flute pool would soften the massive bullet's descent. In practice, you'd better pray A.) that there's not a strong breeze; and B.) that the laws of physics abruptly decide to suspend themselves mid-drop.
See Also: The Euthanasia Coaster.