They had an external means of Ascertaining promptly which way they should go.
"The Expositor's Bible: The Gospel of St. John, Vol. I"
Marcus Dods
Stas was so accustomed to think of Nell in every situation that now he was occupied, above all, in Ascertaining whether she was not in danger of falling, whether she had sufficient room and whether she could lie down comfortably.
"In Desert and Wilderness"
Henryk Sienkiewicz
In this observation, which is so simple that a child may understand it, is a sure and certain means of approximately Ascertaining the North Pole.
"My Attainment of the Pole"
Frederick A. Cook