So lightly and invisibly I hardly knew it,   river of blood descending without joy back to the heart through the frail vein all that time   —the largest of the body—   shredded then dissolved (“obliterated”) and there was a   sudden seepage into the surrounding tissue   instead of the blood pouring out as you’d expect forever before a new vein formed   to bypass what was gone like a wide meander   even the smallest flood ends, and the river goes straight from that point.   But in my case the thin-walled base-ends held   forming an anabranch, a section that diverts from the main channel,   rejoins it downstream.   Local ones can come from, make small islands in the watercourse or flow hundreds of miles   like the Bahr el Zeref in the south Sudan   that splits from the Bahr al Jabal of the White Nile, doesn’t return until Malakal   instead of leaving behind, as it could have   with the blood being old, a full-fledged oxbow lake, a little blue   scar beside the heart.