Mixing Double and Single Track
Because double and single track may use different signalling systems, it may be awkward and confusing to mix double and single track too often. For example, intermediate mechanical signal boxes on a double-track line can be closed during periods of light traffic, but this cannot be done if there is a single-line section in between. This problem is less serious with electrical signalling such as Centralized traffic control.
Read more about this topic: Double Track
Famous quotes containing the words mixing, double, single and/or track:
“Political image is like mixing cement. When it’s wet, you can move it around and shape it, but at some point it hardens and there’s almost nothing you can do to reshape it.”
—Walter F. Mondale (b. 1928)
“Today, San Francisco has experienced a double tragedy of incredible proportions. As acting mayor, I order an immediate state of mourning in our city. The city and county of San Francisco must and will pull itself together at this time. We will carry on as best as we possibly can.... I think we all have to share the same sense of shame and the same sense of outrage.”
—Dianne Feinstein (b. 1933)
“To the query, “What is a friend?” his reply was “A single soul dwelling in two bodies.””
—Aristotle (384–322 B.C.)
“What joy when the insouciant
armadillo glances at us and doesn’t
quicken his trotting
across the track into the palm brush.
What is this joy? That no animal
falters, but knows what it must do?”
—Denise Levertov (b. 1923)