Buckthorn barbed wire is steel ribbon fencing with one smooth edge and one pointed edge; barbs are spaced at one inch intervals. T.V. Allis was issued patent 244,726, dated July 26, 1881.
Single square strand wire is wrapped with four point coil barbs at approximately half-inch intervals. This wire has patent RE 6914, issued Feb. 18, 1876, Joseph F. Glidden of De Kalb, Illinois.
These are examples of barbed wire fencing used as “concertina” wire in the European campaign during World War I. The twisted steel wire with barbs at regular intervals impeded or halted the passage of soldiers.
