In a world where data is coin of the realm, and transmissions are guarded by no better sentinels than man-made codes and corruptible devices, there is no such thing as a secret.
The eyes, like sentinels, hold the highest place in the body. [Lat. , Oculi, tanquam, speculatores, altissimum locum obtinent. ]
Conscience is the sentinel of virtue.
Trees have from time immemorial been closely associated with magic. These stout members of the vegetable kingdom may stand for as long as a thousand years, and tower far above our mortal heads. As such they are symbols and keepers of unlimited power, longevity, and timelessness. An untouched forest, studded with trees of all ages, sizes and types, is more than a mysterious, magical place - it is one of the energy reservoirs of nature. Within its boundaries stand ancient and new sentinels, guardians of the universal force which has manifested on the the Earth. . . .
The eyes like sentinel occupy the highest place in the body.
That virtue which requires to be ever guarded is scarce worth the sentinel.
The stars, bright sentinels of the skies.
Only the soldier pines and sentinels still showed green; the broadleaf trees had donned mantles of russet and gold, or else uncloaked themselves to scratch against the sky with branches brown and bare.
