66561-1920-China-Seas-Storm-Signal-Code — Page 2

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THE HONGKONG GOVERNMENT GAZETTE, MAY 7, 1920.

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Table No. 2.-Condition Signals.

Two upper Symbols of hoist.

‡

Forming.

Two centros.

Direction unknown.

Stationary or very slow.

Recurving.

Filling up.

Table No. 3.-Radius and Intensity Signals.

Radius of position

circles:

120°

The lowest of three Symbols.

60'

I-LTTA

30'

Intensity, etc.: Unknown. Severe.

Unknown. Severe. Deepening. Unknown,

Severe.

Exceptional Continental Position

velocity. depression. uncertain.

Table No. 4.--Time Signals.

Single Symbol at masthead.

Yesterday

morning.

Yesterday afternoon.

This morning.

This afternoon.

Table No. 5.---Gale Signals.

One Symbol at yard-arm.

LT+

Annani Coast.

Gulf of Tongking

Formosan Channel.

Formosa

to

to Swatow.

Yangtze.

Yangize to Shantung Promontory.

Gulf of Pechili and Yalu Gulf.

Sea of

North

of

Japan.

Hokkaido.

East Coast of Japan.

South of Kiushu.

It is important that seamen should realise that the position of the centre of the typhoon as signalled is the position according to the data possessed by the Royal Obser- vatory at the time of the issue of the warning. That data may be as much as 12 hours old. Thus, if the time signal indicates that the warning was issued "This morning," it may be that the position corresponds to data concerning yesterday afternoon.

If the signal "Deepening is made, it indicates that there is reason to believe that the barometric gradient and, consequently, the intensity of the typhoon is increasing.

If the signal "Exceptional velocity" is made, it indicates that there is reason to believe that the rate of progression is 25 per cent. or more greater than the average rate.

If the signal "Position uncertain is made, it indicates that the data possessed is unreliable and that the position signalled is a mere probability.

The several tracks which a typhoon may follow in the several months are very varied, and the velocity of progression is liable to be erratic. It is not safe to count on The a typhoon maintaining a velocity indicated by previous positions of its centre. velocity is liable to increase very suddenly. Seamen are recommended to study from available sources the tracks and average velocities for the month and locality concerned.