Improved Rotary Pump

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.


An improvement on the rotary pump has been lately invented by John Laing, of Brooklyn, N. Y., who has taken measures to secure a patent. In this improved pump the piston is made to work in a recess or slot let into the circular head on the top of the shaft, the circular head being placed eccentric with the bore of the cylinder, which is fashioned of a slightly elliptical form. By this arrangement the length of the piston does not require to be varied, which would ba the case if the bore of the cylinder was made circular. In order that the pump may draw as soon as it is worked, a reservoir or water chamber is placed beside it, with which the supply and feed pipes communicate. The piston, as it rotates, forms a vacuum in the lower part of the cylinder whenthe water rushes in through the supply pipe, which is separated from the discharge pipe by means of the circular head on one side of the cylinder, and the action of the piston bearing against it on the other. The end of the piston, when it passes the orifice of the supply pipe, forces the water around the cylinder into the discharge pipe, and when it has passed this latter, the other end of the piston goes through a similar operation, which is performed alternately by either end as the piston rotates.

Scientific American Magazine Vol 8 Issue 20This article was published with the title “Improved Rotary Pump” in Scientific American Magazine Vol. 8 No. 20 (), p. 156
doi:10.1038/scientificamerican01291853-156

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