I have grouped a number of recently invented water closets into this last class which I consider, in principle, far superior to any of the other closets for the following reasons: They are mostly made in one single piece of earthenware and are entirely free from any movable parts (see Fig. 4, F). Moreover, the bowl of many closets of this type is shaped in such a manner that its outlet or overflow forms a very efficient water-seal trap, thus obviating the necessity of a trap under the closet. All washout closets have their basin so shaped as to hold a large quantity of water; the advantages of such an arrangement have been already stated. A washout closet is in fact only a modified and improved form of hopper.

In England closets of the "washout" type are preferred of late to other closets, and in this country quite a number of such closets have been introduced. Among closets of the washout type mention: The "'National" side outlet closet, Owen's closet, the Lambeth "Flush-out " closet, Carmichael's "Washdown" closet, Woodward's " Washout " closet, Bostel's "Brighton Excelsior" closet, Dodd's Patent closet, Hellyer's "Vortex " closet, the " California " or Smith's " Siphon Jet" closet, the " Dececo" closet, the "Tidal Wave" closet, and others.

Different means are employed with the closets of this class to effect a discharge of the bowl. In many the downward rush of water directed through proper flushing rims so as to concentrate its main force at the outlet of the basin, drives the contents of the bowl into the overflow, and thus into the soil pipe ("Brighton" and " Vortex " closets). In others a jet of water is introduced into the outlet pipe and carries all water from the bowl, partly by the force of the jet, and partly by starting a siphoning action (Smith's "Siphon Jet" closet). In still others a partial vacuum is created by different means in the outlet and a true siphonage established ("Dececo" and "Tidal Wave" closets).