.....or transposition , of an old ...but inonsistent drawing intended to propose a gravity powered device ,at:
https://todayinsci.com/Books/MechApp/chap23/page42.htm
.....at : www.geocities.ws/iacob_alex/Some_Drafts/text036.jpg
As simple as possible , but with a difference...and so easy to test.
Al_ex
.....from : https://youtu.be/6xfgwh-OD1I
.....to. : www.geocities.ws/iacob_alex/Some_Drafts/text035.jpg
Al_ex