experience. Companies of soldiers, persons
collected in asylums, students in a class,
patients in a hospital, private friends, have
been submitted by Dr. Wilson to the test;
and by adding to his researches those of
others, it is made to appear that, on an
average, one man out of fifty is as distinctly
colour-blind as any of the more marked cases
here recited, and that one man in twenty
will err in distinguishing at least among
some of the lighter shades of the mixed
colours. With a bundle of Berlin wools
containing two of every tint, a double series of
tinted papers, or an assorted collection of
small pieces of coloured glass, any one may
cause his own eyes to be tested, or may
bring the eyes of his companions to the test.
Common as colour-blindness proves to be,
oculists in large practice very rarely see a
case. Hundreds are unacquainted with their
own infirmity; many know it, but pay little
heed to it; others conceal it; others, not
caring to talk about it, quietly take measures
to guard against the errors into which they
have found that they are liable to fall.

Our purpose in again calling attention to
the subject is to point out – it cannot be
requisite to urge – the obvious utility of some
adaptation of the practice of railway and
ship-signalling, to the knowledge we now
have of the direction in which eye-service
may so often fail. The eye blind to colour is
even preternaturally sharp as a distinguisher
of form. To the majority of eyes colour gives
the distinctest help, but if there were allied
with every different colour used in signalling
also a different form, common eyes would be
doubly warned, and colour-blind eyes, quick
to observe form, would be nearly, or quite as
serviceable as the rest. A change in the
colours used – which are now green and red
by land and sea – might also be found
advisable. The position of unsymmetrical vanes,
as battle-axes, fishes, broad-feathered arrows,
would be more distinctly read by daytime
than symmetrical signals; and by night, if
the white light were single, the green double,
the red triple, errors of perception would be
difficult. A steam-vessel at sea carries a
white light on the foremast head, a green
light on the starboard side, a red light on the
port side; and any vessel that approaches is
warned by the colour of the light as to the
direction in which this vessel is steaming. A
colour-blind pilot would not know with
certainty whether a red or a green light crossed
his bows. Place two red lights on the port
side in a horizontal line, and two green lights
on the starboard side, on under the other,
and the chance of false perception, on the
score of permanent or temporary colour-
blindness, is removed.

These particular suggestions we give, not
dogmatically, but by way of very simple
illustration. The difficulty against which
provision has to be made being once granted,
and the requisite inquiry instituted, it will
be for the persons who have charge of the
existing plans of signalling to make such
alterations in them as they shall discover to
be sufficient and consider to be best. If no
change be made in the signalling, then, without
doubt, by means of coloured wools or
tinted papers, persons upon whose full and
prompt sense of colour lives will be staked,
must be examined strictly, in order that the
colour-blind may be discovered and excluded
from such trusts. It is obvious, however,
that the interests of the public would be
served most perfectly by a revision of the
railway and ship-signals now in use, for the
purpose of correcting every one that speaks
by colour only.

DR. GRAVES OF WARWICK STREET.

PARK LANE – or that part of Park Lane in
which the Three Crowns Tavern was situated –
was not, a hundred years ago, the fashionable
quarter which it now is. It was chiefly known
for the mountainous cinder-heaps which the
dustmen, who had settled there from unknown
times, had accumulated in waste places by
the roadside. It was a wild, ragged, desolate
region, into which few persons except the
inhabitants of mean houses in the lane, or the
brickmakers or dustmen who lived in wretched
hovels in the fields, would like to venture
after dark. But the Three Crowns was a
good house. It was both a coffee-house and
a tavern, with a bowling-green, and was
frequented much by military men, some of whom
met there regularly at night. The mounted
patrol, who accompanied visitors at night on
their way from Marylebone Gardens,
frequently stopped for refreshment there, and
left one or two of the convoy to swell the
company fellows who liked to finish their
night's amusement with a bowl at the tavern.
They had sometimes, perhaps, less reputable
visitors – for the Three Crowns pryed no
more into its customers' affairs than other
taverns. The man in the laced coat and
jaunty three-cornered hat, who drank and
played with any one who would, might be the
terror of the western roads – mayhap, the
very hero of that dismal paragraph in the
Daily Postboy, which some neighbour would
read to him aloud. When his bill was paid,
and his foot in the stirrup, neither the Three
Crowns nor its company troubled their heads
any further about him.

One evening – it was in the winter time –
there came into the Three Crowns two
strangers of respectable appearance, who
desired to stay there for the night. One
was a man of about forty years of age, of a
short, strong-built figure; he carried his right
arm in a sling. The other was older, of much
larger stature, and evidently a man of great
muscular strength. They attracted little
attention; though it was afterwards
remembered that they remarked to Mr. Bond, the
landlord, that they had just arrived from