780Fs04: "Arrangement for shooting hole through side wall of the tile with a 45-caliber revolver."
Title information from "Improving the Distribution of Water to Farmers by Use of the Parshall Measuring Flume" by Ralph L. Parshall. See Figure 15. Man in leather jacket and hat sitting on bench shooting ceramic tile with revolver. Tile used as stilling well for Parshall flume. Caption further reads, "The distance from base of tile to hole is regulated by blocking up the support to give the correct elevation. The tile as shown is too low for either the Ha or Hb holes."