For heavy gradients rope haulage has no rival, though for moderate grades it is often advantageously replaced by electric and compressed air haulage.
The difference of the temperature gradients D/l at the ends of the section was simultaneously obtained from the difference D of the readings of a pair of couples at either end connected in opposition.
At Such Times Gradients Of 400 Or 500 Volts Per Metre Are By No Means Unusual At Kew, And Voltages Of 700 Or Boo Are Occasionally Met With.
The trains are few and the speed on all these lines is moderate, but the gradients are often very heavy.
The chemical characters of the well-waters, the irregular distribution of the water-pressure, the distribution of the underground thermal gradients, and the occurrence in some of the wells of a tidal rise and fall of a varying period, are facts which are not explained on the simple hydrostatic theory.