Different Degrees Of Heat Imbibed From The Sun's Rays By Cloths Of

different Colours.

Walk but a quarter of an hour in your garden, when the sun shines,
with a part of your dress white, and a part black; then apply your
hand to them alternately, and you will find a very great difference in
their warmth. The black will be quite hot to the touch, and the white
still cool.

Try to fire paper with a burning-glass; if it be white, you will not
easily burn it; but if you bring the focus to a black spot, or upon
letters, written or printed, the paper will immediately be on fire
under the letters.

Thus, fullers and dyers find black cloths, of equal thickness with
white ones, and hung out equally wet, dry in the sun much sooner than
the white, being more readily heated by the sun's rays. It is the same
before a fire, the heat of which sooner penetrates black stockings
than white ones, and so is apt sooner to burn a man's shins. Also beer
much sooner warms in a black mug set before the fire than a white one,
or in a bright silver tankard. Take a number of little square pieces
of cloth from a tailor's pattern card, of various colours; say black,
deep blue, lighter blue, green, purple, red, yellow, white, and other
colours, or shades of colours; lay them all out upon the snow in a
bright sun-shiny morning; in a few hours, the black being warmed most
by the sun will be sunk so low as to be below the stroke of the sun's
rays; the dark blue almost as low; the lighter blue not quite so much
as the dark; the other colours less, as they are lighter; and the
quite white remain on the surface of the snow, as it will not have
entered it at all.

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