The modern bathroom fixture may be made of one of three materials: true porcelain, earthenware, or enamelled-iron. The true porcelain fixtures are the heaviest, the most durable, and the most expensive. The material is non-absorbent and white in color, and the surface presents a gloss which is in reality a form of glass. When it is chipped the fracture shows the material below as white, and a drop of ink will not be absorbed by it. In imitation of the porcelain fixtures are made earthenware ones, but which are in no way to be compared to the true porcelain, although a casual glance at them would lead one to think that they were porcelain fixtures. However, a chip from the surface will reveal the yellow and porous texture of the earthenware below the glazed surface. The glossy white surface in time stains and becomes covered with small hair-cracks, unlike the porcelain fixtures, and for this reason they are not as sanitary nor as durable. They are cheaper than the true porcelain fixtures, but this material should be avoided in water-closet bowls, but is admissible for use in tubs and lavatories. The enamelled-iron fixtures are considered by most to be superior to the earthenware fixtures, since they do not craze, are lighter, and generally more durable. The quality of this ware can be judged by the absence of roughness, blisters, bubbles, and spots, and freedom from hair-cracks and peeling. Bathtubs of the modern type made of enamelled iron have the rich appearance of porcelain fixtures, since the sides are rolled over and covered with enamel, unlike the old-fashioned types, which had the interiors lined with the enamel and the exteriors painted with white paint. The mechanical operation of the various fixtures is so well standardized that not much choice is given between the catalogue of one firm and another. The best type of water-closets are the siphon, the siphon-jet, and the converging jets, the latter being a more modern development, which has eliminated the noise of the siphon action and yet which accomplishes a quick and rapid flushing action. The lavatories which are most commonly specified are of the pedestal type, although the modern tendency in sanitary bathroom design is to eliminate as far as possible all junction of fixtures with the floor, for it is here that dirt and stains develop. Such arrangements carried to the extreme would require a sunk bathtub, a lavatory without legs, and special compartment for the water-closet, but this would be absurd for the small house. However, the built-in bathtub is far superior to the old-fashioned tub which stood upon legs, and under which all manner of dirt could collect.