Why (according to classical physics) do forces compose according to the parallelogram of forces? This question has been controversial; it is one episode in a longstanding, fundamental dispute ...

THE author has already written an excellent book on geometrical statics, and it has been his present object to produce an elementary treatise which shall cover the well-trodden ground of the ...

THIS book consists of a set of graduated exercises in graphical statics. The first seventy, about half the total number, are restricted to problems on the equi librium of three forces at a point, and ...