review the passage. i have seen whence came the expression.'the glassy surface of a lake' when you invert your head it looks like a thread of finest gossamer stretched across the valley, and gleaming against the distant pine woods, separating one stratum of the atmosphere from another. you would think that you could walk dry under it to the opposite hills ,and that the swallows which skim over might perch on it.indeed, they sometimes dive below this line, as it were by mistake, and are undecived which is the best inference once could draw from the passage A thoreau is a tailor b thoreau is interested in language c thoreau is very independent d thoreau has good vision