Among the white-barked gums   Last night possums descended from the white-barked gums to invade your attic, waking you from a drowse and reflections upon a past life where mortar fire forever altered your dreams.   No doubt they heard you whispering to yourself as the wind picked up speed, scrambling away as possums do toward those spots where nocturnal creatures rendezvous.   Your uninvited guests brought to mind memories of who went back for the wounded left behind; and of events that left other bodies abandoned where they fell.   You lay sleepless until all moved on again to…