The stratum of ashes was from 50 cm.
He considered, at every instant, the actual motion of a stratum as composed of a motion which it had in the preceding instant and of a motion which it had lost; and the laws of equilibrium between the motions lost furnished him with equations representing the motion of the fluid.
The second stratum of the town lies ten minutes' climb up the side of the island.
As there are only one or two small stretches of arable land in Ithaca, the inhabitants are dependent on commerce for their grain supply; and olive oil, wine and currants are the principal products obtained by the cultivation of the thin stratum of soil that covers the calcareous rocks.
Symbols like the letters of the alphabet have been found in European soil painted upon pebbles belonging to a stratum between the Palaeolithic and Neolithic age.
