positive current

"Measuring the force," said Keely, "by vibrations, 18,000 of them to a second are necessary to raise that weight through the water. The current that raises the weight is of course a positive current. You see the copper globe remains suspended on the surface of the water. I turn on the negative current." [Pittsburg Dispatch April 07-1890]
Created by Dale Pond. Last Modification: Tuesday October 29, 2013 04:34:12 MDT by Dale Pond.