Crossing currents and the paths of objects in a winding river
How submerged and floating bodies diverge where waters intersect or where the bed curves
Two linked notes, each with a small marginal diagram. In the first, currents cross at different depths: the water d c has a higher bed than the water a b, so objects near the deep bottom of a b pass beneath the shallower stream and hold their straight course, while objects at the surface collide at the surface of d b and have their straight course bent into a curve. In the second, along a winding channel a heavier object dragged near the bottom follows the line a d while a lighter one carried at the surface follows the line b c. The diagrams sit at the upper and middle right of the page.
On this page
Objects carried where two currents intersect (d c over a b)
Where one water enters another above the level of its bed, a thing in the deeper water passes beneath the higher stream. Bodies near the bottom of a b keep their straight course, while bodies at the surface collide at the surface of d b and are deflected into a curve.
Bottom versus surface paths in a winding channel
Along a winding bottom, bodies carried near the bed follow a different course from those carried at the surface. The light object is carried along the bottom by line a d, and the lighter object is carried at the surface by line b c.