Grass of Parnassus ( Parnassia palustris )

Gra -Wrack. See EEL GRASS. Grate Bars for Boilers. These should give adequate support for the fuel, but have sufficient open spaces for air pa age. In large fuels, this proportion should be from 25 to 50 per cent. For small coal, where an exce would fall through, the lack has to be made good by greater intensity of draft. They should also be of a design which will not warp with heat, and deep enough to be kept cool by the inrushing draft of cool air. Usually they are of cast iron, though one form of wrought bar is approved. and water grates of wrought iron pipe are extensively used. Shaking grates give the firemen le exhausting work, and require le frequent and prolonged opening of the fire door. Traveling grates are self cleansing, and can easily be made self-feeding, doing away entirely with the opening of a fire-door and its injury to the shell and the heat of the fire. and also as a top dre ing for roads. Angular gravel is usually better than round. Gravelly soils are finely divided, easily worked, and have many of the characteristics of sandy soils, but are usually more fertile and not quite so quickly affected by lack of water.