"Loschmidt reasoned that in a liquid, the atoms or molecules would be more or less squeezed up against each other, so the volume of a liquid would be straightforwardly the volume of an individual molecule multiplied by the number of them. ...The diameter he came up with was a little less than one millionth of a millimeter—by modern standards a pretty fair answer. ...To critics... Loschschmidt's analysis still didn't prove anything. ...in the absence of tangible evidence that atoms existed, it was mere mathematics, empty theorizing. Loschmidt had shown that if atoms existed, they must have a certain size—but that first "if" had not been overcome."