17
103
The angle depends also upon the distance from the centre, At 25 miles it is 10 points (very uncertain), at 75 iniles it is 11 points, at 125 miles it is 11 points, at 150 miles it is 112 points, at 200 miles it is 12 points, at distances greater than 300 miles the centre bears perhaps about 15 points from the wind (very uncertain).
The angle depends also to some extent upon the latitude though south of Northern Formosa the connection cannot be traced. But in 30° N the average angle is about 10 points and beyond Japan 9 points might perhaps be allowed.
These rules fail, however, near some shores if the centre is not very close. Thus there often blows a steady E gale along the S coast of China when a typhoon is crossing the China Sea. The wind blows into the China Sea through the Balingtang Channel and blows along the S coast of China from E. If the centre is passing to the southward at a distance of several hundred miles, this reminds one of the NE monsoon, but now it blows harder the lower the pressure falls, while in the NE monsoon it blows harder the higher the pressure rises. About the N entrance to the Formosa Channel, one of the windiest places in the world-the gale blows often steadily from NE while there is a typhoon to the S moving westward. Again near the coast of Annam, the wind is likely to hang long about N. This action of the constline in certain localities favours sometimes the birth of a typhoon, thus when the NE monsoon has set in along the S coast of China, and blows from N along the coast of Annam, the SW monsoon (deflected towards the right) is heinmed in by the Island of Palawan and forced into a more southerly direction to the W of Mindoro, and it is found that typhoon centres are formed near that locality; and also SE of Hainan in an area one side of which is exposed to strong E wind coming through the Balingtang Channel, the other to SW winds when pressure is high near the equator.
As far as Hongkong is concerned, the following table, constructed by aid of observations made here during the years 1884-1887 inclusive, gives the details. The first column shows the direction of the wind at the Observatory, the second the direction of the wind at the Peak, the third the direction whence the clouds are coming, and the fourth the bearing of the centre. The results differ from the rules given above because the centre is inland whenever its latitude is greater than that of the Obser- vatory, except far away to the NE, and as soon as the centre of a typhoon enters the mainland it begins immediately to fill, ceases to exist as a typhoon, and can be traced as only a slight depression:-
Wind
at the Observatory.
Wind
at the Peak.
Clouds.
Centre.
E by N
NNE
NW by N
E
E
S
NE
NE
SE
N
N
E
W by N
NW by W (?)
NW by W
NE
SW by W S by W
W by S
WSW
N
SE by S ESE
SW by S S by E SE by E
SW by S
NW
S
W
SE
SW
N
W
S
A Typhoon in Hong Kong.
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