distinguishable

At the other end, silent, scarcely visible, and like a shadow, was a sentinel, who was walking up and down before a grotto, which was only distinguishable because in that spot the darkness seemed more dense than elsewhere.

On reaching La Storta, the point from whence Rome is first visible, the traveller evinced none of the enthusiastic curiosity which usually leads strangers to stand up and endeavor to catch sight of the dome of Saint Peter’s, which may be seen long before any other object is distinguishable.