At the first outset, heavy, miry ground and a matted, marsh vegetation greatly delayed our progress; but by little and little the hill began to steepen and become stony under foot, and the wood to change its character and to grow in a more open order.
"Treasure Island"
Robert Louis Stevenson
This is true of the rocks up to the level of the Chimney, but they steepen when that is passed, and remaining smooth and with but few fractures, and still continuing to dip outwards, present some steps of a very uncertain kind, particularly when they are glazed with ice.
"The Ascent of the Matterhorn"
Edward Whymper
When he had gone the better part of a mile into the country, and the road had begun to steepen perceptibly, the sound of a motor behind warned him to one side.
"The Turner Twins"
Ralph Henry Barbour