Abstract: The tennis court has water impervious bays which contain water distribution piping and particulate material that conducts water from the bottom of the bays upwardly by capillary action to the playing surface of the court. The water distribution piping includes a substantially rigid outer pipe having relatively large openings extending through its lower portion, and at least one inner pipe that is located within the outer pipe and that has a plurality of water discharge orifices at spaced locations along its length. Water from a supply source is introduced into the inner pipe, at a desired low pressure and flow rate, at those times when a moisture sensor determines that the sensed moisture content within the particulate material adjacent the playing surface of the court is less than a preselected desired magnitude. Valving associated with the water distribution piping permits purging and/or draining of the piping.

Abstract: A mobile coal-fired fluidized bed furnace system (10) is provided for generating steam to power a locomotive. Coal is combusted within the fluidized bed furnace chamber (30) in the fluidizing air to produce a hot flue gas which pass from the furnace chamber (30) through a boiler tank (90) and an economizer (34). The steam generated in the boiler bank and the walls of the furnace chamber is collected in steam drum (40) and passed therefrom through an in-bed superheater (100) and thence to the power generating means (22) to produce the power which drives the locomotive.