This is probably a good example of some of the uncertainties involved in making the earliest motion pictures, particularly the 'actuality' kind that showed largely unprompted footage of daily life. In this case, the setup is good, the subject is interesting and potentially entertaining, yet it ends up being a rather plain movie for the most part.
The footage shows activity on a water ride at Coney Island, the kind of "Shooting the Chutes" ride that was as popular then as it is now. There are a good many movies from the late 1890s and early 1900s that show very similar scenes. Not only Edison, but also Lubin and American Mutoscope made films of this or similar rides, both at Coney Island and in other locations.
In this feature, the camera angle is well chosen, from a vantage point that brings the main motion towards the viewer at a diagonal angle, the technique that the early Lumière features had demonstrated to be so effective. The composition is also good, catching a pretty long stretch of the chute, plus a clear view of the track alongside on which the empty boats are hauled back to the top. But after setting up everything so carefully, except for the first few seconds not much happens, and soon the film runs out.
According to the notes in Kino's recently released collection of Edison films, there was also a 150 foot version (as opposed to this 50 foot version) made at the same time, and perhaps the longer version was more fortunate in catching some more interesting action. But only this rather bland shorter version seems to be available at present.