the bottom quantified: out of vein, cooking with urine — "They ran out of the distilled…"
They ran out of the distilled water Fackelmann had in the mixing bowl, and Fackelmann took a cotton and sopped up candy-dyed urine off the floor and cooked up with urine. Gately appeared to himself to be repulsed by this.
Context
The bottom rendered as pure physical data, no sermon: so many injections in one arm that the veins give out and he moves to the other, then — the distilled water gone — cooking the next shot up out of the piss they've been sitting in. The tell is the smallest clause, "appeared to himself to be repulsed" — even the disgust is at one remove, observed rather than felt, which is how far the Substance has taken the man from his own reactions. This is the lived floor under every AA position Gately will later hold; he earned the doctrine here, on a urine-corroded oak floor.