the oil-cooler, while the ammonia, still in a gaseous state, ascends to the ammonia condensers on the top-floor of the building. By the use of salt water on the outside of these condensers, the ammonia is reliquified, and in this liquid state again descends to the cellars, as before described. Still another circle within a greater circle! A recapitulation of the functions of this refrigerating plant may not be out of place. It cools 1,750,000 cubic feet of space in cellars; supplies ice-cold water for the attemperators in fermenting tuns and reduces the temperature of the wort, as it passes over the cooling pipes, to 40° Fahrenheit. During the summer months the beer to be cooled, in the latter manner, amounts on an average to two thousand barrels, daily—the maximum daily brew being twenty-seven hundred barrels.[5] [5] Multiplied by four, these figures give _present_ output. [Sidenote: THE STEAM PLANT] The steam required in this brewery for all the operations already described, and others still to be spoken of, is generated by eight colossal boilers, each five and a half feet in diameter, and containing fifty-six four-inch tubes. They are of the horizontal return tubular type, fitted with patent furnaces and water arches, and rated at 130 horse-power, each. This boiler plant is really of double the capacity needed, and, hence, only one-half of the number of boilers is alternately in use, the other half being provided as a reserve in case of emergencies. The steam generated in these boilers drives fourteen engines. Of these, one is used in the machine shop; three serve the purposes of the refrigerating plant; two are used for the electric-light plant; three, varying from 100 to 165 horse-power, set in motion the mashing apparatus, the malt-mill, malt elevators, keg-washing machines, rotary pumps in cellar, two Otis belt elevators and four keg elevators. Two of the latter are used for lowering empty kegs into the cellar, and the other two for raising filled kegs. In addition to these, there are four more engines, one each for driving a feed-grinder and fodder-cutter in the stables, a set of revolving and suspended fans in the office, the cask-rollers in the pitch-yard and the machine for washing chips. All these steam motors, as well as the refrigerating machines, are connected with that system of steam condensation to which we referred in describing the partial heating of brew-water by means of exhaust steam. Previous to condensation the exhaust-steam passes from the engine through an apparatus, called grease extractor, which eliminates the oil; it is then conveyed to a Gannon surface condenser and thence returned to the boilers. In this process of condensation a vacuum of from twenty-five to twenty-six inches is produced by means of an air-pump. The immense quantity of salt water used daily for the condensers of ammonia is so profitably utilized in this manner, that condensation is effected without an extra supply of water.