Comment on Eisenthal's 'mechanics without mechanisms'.

In a recent paper on Hertz's Mechanics, Eisenthal claims that this mechanics is without mechanisms. He argues that the absence of mechanisms is a consequence of Hertz's philosophy of physics, presented in the introduction to this book. In the present paper, I will show that Hertz created four mechanisms. These mechanisms play a fundamental role in the deduction of the equations of motion. Some physicists used these mechanisms to create Hertzian mechanical models or to apply Hertz's mechanics to phenomena.