There are many parts of the railway business which are interesting in their own right and which questions are asked about from time to time. This page looks at detailed parts of equipment, systems, standards, dimensions, procedures and infrastructure in no particular order. New items will be added from time to time.
The Ediacaran Period ( /iËdiËÃ¦kÉrÉn/), spans 94 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 541 Mya. It marks the end of the Proterozoic Eon, and the beginning of the Phanerozoic Eon. It is named after the Ediacara Hills of South Australia.
The Cambrian Period was the first geological period of the Paleozoic Era, of the Phanerozoic Eon. The Cambrian lasted 55.6 million years from the end of the preceding Ediacaran Period 541 million years ago to the beginning of the Ordovician Period 485.4 mya. Its subdivisions, and its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latinised form of Cymru, the Welsh name for Wales, where Britain's Cambrian rocks are best exposed. The Cambri