The speaker begins with a literary image: Chinese drunken poets who longed to see their reflections in the clouds, as if drink could turn the sky into a mirror. Today the wish can't be met. There are no clouds, only a sky "as clear as gin," a sharp comparison that makes the sky and the drink the same thing. It is something "to swim or drown in," and the line holds both the pull of drinking and its danger.
Then the poem turns. A short line, "the river takes this bend," moves attention to the ground, and the final lines say that air and water "don't meet as friends." Judging by the imagery, the speaker may be sensing a gap between the dreamy, intoxicated ideal and the real world, where sky and river stay apart. The mood is quiet, dry and a little wary. There is longing for an old, romantic kind of drunkenness, but also a cool awareness that nothing will reflect the speaker back today.