Photograph of 2 hot water tanks and 2 men, Southern California, 1928. "Serial N[umber] [ilg], Size & Actual Cap[acity] [ilg] Gal[lons], Patent Appl[ie]d For, Hoyt, Reg[istered at the] U.S. Pat[ent] Off[ice], Test Pressure 300 Pounds, Working Pressure 125 Pounds, Burner Rating Per Hour [ilg] B[ritish] T[hermal] U[nits], Super Series Storage Automatic Gas Water Heater, Caution, Should pilot light become extinguished [thru] any cause follow the above instructions, Open drain cock once every thirty days and draw off two to three gallons of water, Hot Water, Important, [In the event a check valve or pressure regulator is installed on cold water inlet lines a pressure relief valve should be placed on heater], San Jose, Hoyt Heater Company, San Diego, Los Angeles, Oakland, San Francisco, Portland, Long Beach" -- written on hot water tank.