== isolated system and gravity == 

 The present article says that an isolated system is completely isolated. There are many cases in which one wishes to consider a system that is not allowed to see transfer of matter, heat, or pressure-volume work, but one does wish to allow a gravity field to permeate the working body. Sometimes people speak of an isolated system with no external long-range force field acting on it. I think the article should perhaps allow an isolated system with an external long-range force field acting on it? According to Crawford (1963), on page 5, referring to this, "there is no insulator against gravitational fields. Hence we must rule out gravitational effects altogether." But the Maxwell-Boltzmann distribution does consider external long-range force fields. This calls for some thought, and a look at the literature, to see how to deal with it in the article, I think.