Page:Popular Science Monthly Volume 56.djvu/547

Rh ment which may be seen in that city considerable sections must have floated away. The round block has nothing to recommend it but its cheapness, and this usually proves to be expensive economy. In Galveston, Texas, creosoted yellow pine blocks have been laid for some years with general satisfaction. They are laid directly on the fine sand, which is water-rammed so as to be very compact. The surface is formed with great care by a template to the exact



grade and crown, and the joints are filled with similar fine sand. In Indianapolis creosoted blocks have been laid for several years, sixty thousand square yards having been put down during the past season. They are laid as closely as possible on a concrete foundation, with a sand cushion of one inch, and the joints filled with paving cement, composed of ten per cent of refined Trinidad asphalt and ninety per cent of coal-tar distillate, after which