 Second, one must be careful in understanding just how the argument works, for it is tempting to gloss it by saying that in Newtonian mechanics the affine connection is a crucial part of the explanation of the surface of the water in the bucket, and if the spacetime which carries the connection is denied, then the explanation fails too. But this gloss tacitly assumes that Newtonian mechanics can only be understood in a substantial Galilean spacetime; if an interpretation of Newtonian mechanics that does not assume substantivalism can be constructed, then all Newtonian explanations can be given without postulating a connection in an ontologically significant sense. Both Sklar (1974) and van Fraassen (1970) have made proposals along these lines.