Improved Tide Mill

Join Our Community of Science Lovers!


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Measures to secure a patent for the above have been taken by John Smith, of Parmelia, N. Y. The apparatus which forms the subject of this invention differs from the ordinary tide mills, in being altogether independent of any return or current. It may be employed in any tidal water, and is particularly well adapted for use in harbors and docks, for the purpose of driving hoisting machinery for loading and unloading ships. It consists of a vessel or float of adequate buoyancy, which is confined by any suitable means so that it can only move vertically. It carries a vertical toothed rack gearing with a pinion, so placed as to be capable of giving motion to the machinery, which the power is to drive, or is furnished with other suitable means of transmitting the same as it rises and falls with the tide. In order to obtain the same amount of power at the above different changes, it is necessary that the weight of the float should be sufficient to produce the required power, and that it should be sufficiently buoyant to bear at least an equal amount of additional weight, these two desiderata being regulated by the admission of a certain quantity of water to the interior of the vessel.

Scientific American Magazine Vol 8 Issue 27This article was published with the title “Improved Tide Mill” in Scientific American Magazine Vol. 8 No. 27 (), p. 212
doi:10.1038/scientificamerican03191853-212

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe