I read in Newton and the Counterfeiter about the young mathematician who was friends with Sir Isaac and competent enough to have detected an error in Principia.
He offered a theory of gravity, I believe that is more or less identical to that of Le Sage and at first look (to me) is fairly compelling: That invisible particles are moving throughout space, exerting pressure on objects -- what we see as gravity is the "shadow effect" when one body blocks the particles on one side.
I understand that one objection which came much later is how such particles would heat bodies -- don't think anyone understood the idea that heat could be generated in this way in the 17th century. But the book mentions that two contemporaries of Newton who were also "natural philosophers" found this idea amusing and did not take it seriously.
But given that this idea resurfaced after de Dullier (and maybe more than once even in the 19th century in a different form) just what was the basis for 17th/18th century physicists being so dismissive?
To be clear, I am not interested in objections that occurred much later but rather those of the 17th and early 18th century physicists who first encountered Fatio's work.