Then he ascertained that the heart was a pump and that the valves in the veins prevented backflow and he followed the course of the circulation.
"Our Legal Heritage, 4th Ed."
S. A. Reilly
The valves in the veins prevented backflow.
"Our Legal Heritage"
S. A. Reilly
Mr. Waples sank along the sides of the cave in the swash or backflow, until he arrived at a grand archway of limestone, riven from a mass of slate.
"Tales of the Chesapeake"
George Alfred Townsend