The Saint Paul globe., 1905-04-30

by c. E. Wood. and A. c. Eneas, and N.
B. Gale. the electrical engineers and lat
terly by Prof, Lucius /. Blake OF the Uni
versity of Kansas, who is now a consult
ing engineer for the company.
The first object Mr.. Mundy had in
view was to make it an effective device
for signaling in fogs and storms. Despite
foghorns, bell buoys and whistling buoys,
vessels are constantly going ashore through
failure to hear these warning signals.
Currents Of air of differing intensities
shift and vary the sound so that they at
times are utterly unreliable, while water
as a sound conductor is a medium that
works invariably. Even wireless teleg-
raphy fails to work under certain atmos-
pheric conditions.
Mr.. Mundy presented his invention to
the lighthouse board on the ground of its
usefulness as a life saving device. Supt.
Arthur p. NoZro of the department of the
east sanctioned 1t, and permission was
given to install submarine bells in Boston
harbor. The present system of signal bells
on lightships from Delaware breakwater
to Portland is the result.
The Canadian government has put the
device into operation on one lightship at
Yarmouth, n. s., and five lightshiPs in
the st. Lawrence river, and is at present
installing II at fifty other points on the
bay of Fundy and Nova Scotia coasts.
Boston harbor now has a submarine
signal bell not only on Boston lightship,
but a similar bell anchored on Harding s
ledge. off Point Allerton. Another sub
marine bell will soon be placed in the
middle of the ship channel opposite Bos-
ton light. 1t will be sunk deep enough to
allow all vessels to go directly over it.
Sailing masters can then lay a course
straight for this bell in thick weather
AT present they have to calculate their
position by the bell on Boston lightship.
The system of signaling now in use
along the New England coast consists in
ringing signal bells from all the light
ships. These bells toll out the numbers of
the different lightships, 81 for Boston. 73
for Pollock Rip shoals sc for Nantucket
shoals. etc. There is an interval OF two
seconds between each beat OF the bell
four seconds between numbers, and six
seconds before the code is repeated. These
bells are rung by steam pressure and
work automatically. In clear weather
there is no need for sounding the warn
Ing bell. They are rung only when the
weather thickens and the forghorns are
started
Vessels coming up from New York by
the Vineyard in foggy or squally weather
listen first for the bell on Vineyard
sound lightship. tolling out IL. Getting
her bearings here, she has a good chance
OF laying a proper course for Pollock
Rip shoals. where another guiding bell
may be heard.
How Signals Are Heard on the Ships
/ The mechanism for hearing these signal
! bells in the pilot house of a ship looks
much like an ordinary telephone at first
glance; but. instead of one receiver there
! are two, one hanging on either side OF
the box. as an extra precaution in case
one should get out of order
The sailing master nearing a port or a
| dangerous reef where a lightship is an
chored takes down a receiver and moves
lever first to one side and then to the
| other. The side through which the sound
comes indicates that the bell is on that
side of the ship. Curiousiy enough, sound
! will not travel through a corner under
water: it moves in straight lines. Or IT,
/ like light. it be reflected, it is so weak
| as to be readily distinguishable from the
! sound coming from the same object in a
/ direct line.
1t has been found that the exact posi-