heat from the body of a man or other animal in an adjoining field, and
can do so at great distances. It will do this equally well at night,
and may be said, in a certain sense, to give the power of seeing in
the dark." (_Science_, issue of Jan. 8,1881, p. 12.) It is expected to
reveal great facts concerning the heat of the stars.

Indeed, the thermopile in the hands of Lockyer has already made palpable
the heat of the fixed stars. He placed the little detective in the focus
of a telescope and turned it on Arcturus. "The result was this, that the
heat received from Arcturus, when at an altitude of 55 deg., was found to be
just equal to that received from a cube of boiling water, three inches
across each side, at the distance of four hundred yards; and the heat
from Vega is equal to that from the same cube at six hundred yards."
(Lockyer's Star Gazing, p. 385.) Thus that inscrutable mode of force
heat traverses the depths of space, reaches the earth, and turns the
delicate balance of the thermopile. Another discovery was made with the
spectroscope; thus, if a boat moves up a river, it will meet more waves
than will strike it if going down stream. Light is the undulation of
waves; hence if the spectroscope is set on a star that is approaching
the earth, more waves will enter than if set on a receding star, which
fact is known by displacement of lines in the spectroscope from normal
positions. It is found that many fixed stars are approaching, while
others are moving away from the solar system.

We cannot note the researches of Edison, Lockyer, or Tyndall, nor of
Crookes, who has seemingly reached the molecules whence the universe is
composed.

The modern observatory is a labyrinth of sensitive instruments; and when
any disturbance takes place in nature, in heat, light, magnetism, or