THE INTERNATIONAL CODE OP SIGNALS 659
The SOUTH Cone (point downwards) is hoisted for gales commencing t
from a Southerly point; such gales often veer, sometimes to as far as
North-west.
For gales commencing from East to West the SOUTH cone will be
hoisted if the gale is expected to change to a southerly direction.
The NORTH Cone (point upwards) is hoisted for gales commencing
from a Northerly point; for gales commencing from East or West the
NORTH cone will be hoisted if the gale is expected to change to a northerly
direction.
RADIO SIGNALS. VOLUME 11.
The radio signals are arranged $n five-letter groups representing
various words, phrases and sentences which might be required to
transact ship's business by wireless telegraphy. In common with all
telegraphic codes it is necessary to be familiar with the contents and
arrangement of the book in order to obtain from it the most accurate
and economic results. The Code groups and the text are arranged
alphabetically side by side, and a Table is provided so that the receiver
may be able to trace and to rectify an error in a mutilated group as the
Code groups are constructed on an arithmetical system that will ensure
that they will differ from one another by at least two letters and that
no two groups can occur containing the same five letters with a pair
of adjacent letters inverted.
When International Code Signal groups of letters are to be trans-
mitted by radio the message is preceded by "/ N T G 0" to indicate
that the following is coded from the International Code of Signals.
Bearings, courses numbers, latitude, longitude, time, etc., are expressed
in five-letter Code groups.
When a message is to be sent a series of Code groups are selected to
make up the desired message, the following being an example, taken
from the Medical Section, of one ship asking from another the assistance
of a doctor.
M O G A J I have a sailor
KU EBP Age 18
MOV MI has compound fracture of
NANNU thigh
M 0 T B A bleeding severely from wound
M 0 TOM but has been arrested temporarily by tourniquet
M O T U V bleeding cannot be stopped
NIM A. G Will your doctor come on board