Development
As locomotives became more numerous the need arose to deal with them in groups of similar engines rather than as named or numbered individuals. These groups were named "classes" and at first tended to reflect capability rather than design. For example, the Baltimore and Ohio Railroad grouped its roster into four classes before the Civil War, though they had by that point dozens of different designs.
Later classes were based on design. A group of locomotives built off the same blueprints constituted a class, and if some of the locomotives in the class were sufficiently modified, a new class might be established for the modified examples. When electric locomotives were introduced, the same scheme was applied to them.
Since steam and early electric locomotives were usually custom built, classes were assigned by the railroad, and each railroad had its own system. Mergers of lines and sales of locomotives brought about changes of class. Early diesels were often fitted into the locomotive class system, but since they were generally not custom built the use of manufacturer model designations overtook the class system and made it irrelevant, except for historical discussion.
Read more about this topic: Class (locomotive)
Famous quotes containing the word development:
“To be sure, we have inherited abilities, but our development we owe to thousands of influences coming from the world around us from which we appropriate what we can and what is suitable to us.”
—Johann Wolfgang Von Goethe (1749–1832)
“Theories of child development and guidelines for parents are not cast in stone. They are constantly changing and adapting to new information and new pressures. There is no “right” way, just as there are no magic incantations that will always painlessly resolve a child’s problems.”
—Lawrence Kutner (20th century)
“As a final instance of the force of limitations in the development of concentration, I must mention that beautiful creature, Helen Keller, whom I have known for these many years. I am filled with wonder of her knowledge, acquired because shut out from all distraction. If I could have been deaf, dumb, and blind I also might have arrived at something.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)