Closed Circuit Rebreathers

Famous quotes containing the words closed and/or circuit:

    Alas for the cripple Practice when it seeks to come up with the bird Theory, which flies before it. Try your design on the best school. The scholars are of all ages and temperaments and capacities. It is difficult to class them, some are too young, some are slow, some perverse. Each requires so much consideration, that the morning hope of the teacher, of a day of love and progress, is often closed at evening by despair.
    Ralph Waldo Emerson (1803–1882)

    Within the circuit of this plodding life
    There enter moments of an azure hue,
    Untarnished fair as is the violet
    Or anemone, when the spring strews them
    By some meandering rivulet, which make
    The best philosophy untrue that aims
    But to console man for his grievances.
    I have remembered when the winter came,
    Henry David Thoreau (1817–1862)