of the above-named instances some error
may have arisen, without any impeachment
of the honesty of the observers
Nevertheless, it was a capital bonfire, such
as England had not seen for many a day.

As to real signal bonfires, we know that
in the feudal times, and in the earlier days
of England as well as other countries,
beacons were often kindled on hill-tops.
The novels and poems of Scott will bring to
mind many illustrative instances, mostly
relating to alarm-signals in periods of war
and danger. There are two lines by
Macaulay in which this very Malvern Hill
is spoken of:

       Till twelve fair counties saw the blaze
        From Malvern's lonely height!

Charnock, in his Marine Architecture,
states that in the times of the Byzantine
emperors, signals were made and answered
by means of beacons erected in proper
positions, from mountain to mountain,
through a chain of stations which
commanded an extent of five hundred miles;
whereby the inhabitants of Constantinople
were enabled to ascertain, within the short
space of a few hours, the movements of their
Saracenic enemies at Tarsus. The beacons
were sometimes formed of faggots of wood,
sometimes of vessels of pitch; while tallow,
oil, and other combustibles, were employed
as occasion or necessity demanded.

Concerning the possibility of seeing
artificial light at a great distance, the
Ordnance Survey furnishes the most
interesting and trustworthy experience. It
is necessary, in the highly scientific details
of such a survey, that certain elevated
spots should be rendered visible at great
distances one from another, for the
determination of large triangles of which the
angles can be accurately measured. The
custom has generally been to wait for a
clear sky, and then to employ a powerful,
telescope to view the summit of a distant
mountain. When Colonel Colby was
placed in charge of the Irish Ordnance
Survey in 1824, he at once saw the
necessity, in so misty a climate as that of
Ireland, of employing some intense artificial
light to render the stations visible one from
another. Lieutenant Drummond had,
shortly before that period, conceived the
idea that the almost unapproachable light
of incandescent lime, reflected from a
parabolic mirror, might be used as a night
beacon; and Colby and he thereupon
proceeded to test the theory in practice. A
particular station, called Slieve Snaught,
in Donegal, had long been looked for
from Davis Mountain near Belfast, a
distance of sixty-six miles. The mist, day after
day, was too great to permit it to be seen;
and then Colby determined to employ
Drummond's light. The night selected
was dark and cloudless, the mountain was
covered with snow, and a cold wind gushed
across the wintry scene. Colby was on
Davis Mountain, Drummond on Slieve
Snaught; on the instant the latter
displayed his lime light, the former saw it
as a brilliant star, shining over the
intervening Lough Neagh. It was a complete
success of a beautiful experiment. The
light was produced by placing a small ball
of lime, only a quarter of an inch in diameter,
in the focus of a parabolic mirror, and
directing upon it (through a flame arising
from alcohol) a stream of oxygen gas; the
lime became white hot, giving out a light,
the intensity of which alike surpassed
conception and description. It is literally true
that a tiny bit of lime was visible sixty-six
miles distant; for it was not flame that
was seen, but the actual white-hot lime
itself. The experiment having once
succeeded, it was applied in various ways.
One of the famous triangles established by
Colonel Colby had for its three points Ben
Lomond in Dumbartonshire, Cainsmuir in
Kirkcudbrightshire, and a mountain in
Antrim in Ireland; each station was
rendered, by the lime light, visible from
each of the other two, although the
distances were sixty-seven, eighty-one, and
ninety-five miles respectively. On another
occasion he even exceeded a hundred miles,
by this wonderful light.

The ordnance surveyors have also
succeeded in rendering their far distant
stations visible in the day-time, by a peculiar
employment of sunlight. Small pieces of
polished tin, speculum metal, silvered
copper, or looking-glass, are so fixed in
apparatus, that the sun's rays may be reflected
in a line leading f;o the distant station,
where a telescope renders the ray visible.
Little gleams of sunshine have thus been
rendered visible at distances exceeding a
hundred miles. If we doubt, therefore,
some of the alleged achievements of the
Malvern bonfire, it is only because we doubt
whether the light, though large enough,
was intense enough.

There is now coming into use, for miliary
purposes, a simple and handy visual
or visible signal available for short
distances. Up to a certain range, and by
daylight, it can be used without any
apparatus whatever, except the two arms of a
soldier, stretched out in definite directions.
For longer distances a hand-flag, a circular