FTR is a British rapid-transit bus system, currently in operation in Leeds, Luton and Swansea.irst Group has introduced the system, using Wright StreetCar articulated buses in conjunction with infrastructure upgrades by local authorities. The vehicles have been branded as the future of travel, the operators claiming that ftr is textspeak for the word future.
Limestone is a sedimentary rock, composed mainly of skeletal fragments of marine organisms such as coral, forams and molluscs. Its major materials are the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO3).
Limestone is common a rock that makes up about ten percent of all sedimentary rocks. Limestone is made up of calcite aragonite. A lot of limestone comes from skeletal fragments of marine organisms. Throughout history, many people have recognized limestoneâs potential and used it for a building material.The great pyramids of Egypt, among many other landmarks, are constructed of limestone.o make Portland cementâthe most common type of cementâpowdered limestone is heated in a rotary kiln. As a source of calcium, it joins with powdered clay to produce a product called clinker, which is then ground with a source of sulfate, like gypsum.