M
Le, the centre of the isobars,
16
17
335
The force of the wind is also different according to the dimension of the typhoon. On an average The angle depends also upon the distance from the centre. At 25 miles it is 10 points (very have force 12 within 35 miles of the centre, force 11 at 50 miles, force 10 at 75 miles, force 9 at certain), at 75 miles it is 11 points, at 125 miles it is 114 points, at 150 miles it is 113 points, at miles, force 8 at 145 miles, force 7 at 180 miles, force 6 at 220 miles, and force 5 at 250 miles; but it of 0 miles it is 12 points, at distances greater than 300 miles the centre bears perhaps about 15 points blows force 6 at 300 miles from the centre and then the area with strong wind is increased in proportion the wind (very uncertain).
Within from 2 to 15 miles of the centre the wind calms down, or nearly so, and the sky us The angle depends also to some extent upon the latitude though south of Northern Formosa the
ection cannot be traced. clears overhead, more or less, at sen (or over an island), being now covered there by only very
But in 30° N the average angle is about 10 points and beyond Japan 9 clouds or haze, through which the sun or the brighter stars are visible. The sea is often seen to Mints might perhaps be allowed, like a cauldron. Its surface has been whipped into foam, and a lot of air has been caught by the way These rules fail, however, near some shores if the centre is not very close. Thus there often which escapes under the low air pressure in the ball's eye of a typhoon. The sea is as a rule moows a steady E gale along the S coast of China when a typhoon is crossing the China Sea. The tainous and confused, but sometimes near land it calms down when the diameter of the calm and blows into the China Sea through the Balingtang Channel and blows along the $ coast of China exceeds 20 miles. Quantities of sen-birds, and, closer to the shore, also land-birds, butterflies, an E. If the centre is passing to the southward at a distance of several hundred miles, this reminds other insects cover a ship caught in the centre of a typhoon. The centre of the calm area, rose of the N monsoon, but now it blows harder the lower the pressure falls, while in the NE which the wind circulates, does not always exactly coincide with the point where pressure is lows onsoon it blows harder the higher the pressure rises. About the N entrance to the Formosa It has been found that the calm followed some 20 miles after thannel,-one of the windiest places in the world-the gale blows often steadily from NE while lowest barometer reading, but such is not always the case, and the reverse has been suspected on here is a typhoon to the S moving westward. Again near the coast of Annum, the wind is likely to This action of the coastline in certain localities favours sometimes the birth of a than one occasion. Very deceitful Julls occur during the raging of a typhoon. They last someti ang long about N. long enough to be mistaken for the central calm, but when the wind rises again it comes from earphoon, thus when the NE monsoon has set in along the S coast of China, and blows from N along the same direction. Thus in case of typhoons moving W or NW in the China Sea in summer the coast of Annam, the SW monsoon (deflected towards the right) is hemmed in by the Island of is sometimes an area, some 60 or 70 miles behind or to the S of the centre, where the wind falls to Palawan and forced into a more southerly direction to the W of Mindoro, and it is found that typhoon fresh or strong breeze, which again increases rapidly and even a couple of hundred miles farther entres are formed near that locality; and also SE of Hainan in an area one side of which is exposed The diameter of the central calm in a low latitude in sumstrong E wind coming through the Balingtang Channel, the other to SW winds when pressure is it blows stronger than over that area, is about 4 miles, and the sca is mountainons from all directions, but farther north or late in the wigh near the equator. the diameter reaches sometimes from 40 to 50 miles, and the sea then often goes down together As far as Hongkong is concerned, the following table, constructed by aid of observations made The weather becomes dere during the years 1884-1887 inclusive, gives the details. The first column shows the direction the wind, but the character of the bull's eye is then less well defined. though in one or two cases torrential rain has been registered within the central calm. Inland in the wind at the Observatory, the second the direction of the wind at the l'eak, the third the direction hence the clouds are coming, and the fourth the bearing of the centre. The results differ from the the bull's eye has never been observed.
When the wind rises in a typhoon it blows in gusts and the mercury heaves in the baromele les given above because the centre is inland whenever its latitude is greater than that of the Obser- When the wind has reached force 11 it blows in fierce squalls of sometimes about 10 minutes' datery, except far away to the NE, and as soon as the centre of a typhoon enters the mainland it begins tion, while the mercury heaves up and down as much as a tenth of an inch. The mercury of mmediately to fill, ceases to exist as a typhoon, and can be traced as only a slight depression: gives a jump upwards as the wind begins to veer in a squall. Then it drops down and gives anothe upward jump as the wind comes back to nearly its old direction. During these squalls an enormo quantity of rain falls in a few minutes. The temperature falls and rises a fraction of a degree or m The wind does not return to quite the former direction, except just in front of the centre. At time when the centre is nearest, a fierce squall is usually felt, and in that squall the direction of wind changes considerably, and the barometer begins to rise. The squalls appear to be caused by s
As the air comes rushing down the rain drops evaporate in up-and-down movement of the air. hotter stratum near the earth's surface, and owing to the increased tension of water-vapour, i barometer (after a fall caused by the cold of evaporation) begins to rise. The wind veers tovan the direction of the wind above, which latter is known from the motion of the clouds. Then the a starts to rise with a deluge of rain, caused by the condensation of vapour arriving at the c stratum above, while the barometer (after a rise caused by the heat of condensation) drops dor owing to the cessation of the pressure of water-vapour condensed into the rain fallen, and the w resumes the direction determined by the central depression; for the latter is so great in a typhoon a gradients so steep near the centre that subsidiary depressions have never occurred in the China Se
It is a fact that more damage to vessels is caused by the fearful seas than by the wind. F tunately masters of ships are now making use of oil to calm the waves, a remedy which has be used with good effect for the last three thousand years. Thick oil is best-mineral oil is of no use and it should be allowed to ooze out of canvas bags half full of cotton waste and slung from
It is still w weather bow, or it may be left to ooze ont of other openings, such as water-closets. effective when fired from the vessel towards approaching seas from mortars or rockets.
On shore perhaps as much damage is caused by rain as by wind; but, of course, the former a impetus to the latter. The wind blowing from all sides, into the centre raises the level of the there, and the sen-surface is also raised about a foot for every inch the barometer falls below its he outside of the typhoon. When this storm-wave approaches the shore near the time of high wald which somehow seems to happen rather often, it raises the sea, and is apt to cause extensive s disastrous inundations over low-lying shores, as the crests of the waves (which at sea may be 30 i high or more) on entering shoal water may rise 60 feet or upwards above sea-level in a typhoon.
The incurvature of the wind in a typhoon depends upon the monsoon.
In May, June, July, August the angle between the wind (direction whence coming) and the hearing of the centre is points in front of the centre, 10 points in the right-hand quadrant, 12 points behind the centre 114 points in the left-hand quadrant. During September, October, and Novembar it is 11 points This shows that the monsoon blowi front, 11 to the right, 12 in rear, and 11 points to the left. towards the centre and combines with the cyclonic winds. It will be remarked that the wind bi across the path in front and helps a vessel to run across the path in front of the centre, keeping
straight In rear the wind blows more st wind on the starboard quarter 3 points from the stern, towards the centre, and it also blows stronger in rear than in front.
Wind
at the Observatory.
E by N
NNE
NW by N
W by N
SW by W
S by W SE by S
ESE
W
Wind
at the Penk.
E ΝΕ N
Clouds.
Centre.
E NE
S
SE
N
E
NW by W (?)
NW by W
NE
W by S
WSWY
N
SW by S
SW by S
NW
S by E
S
W
SE by
SE
SW
N
$
A Typhoon in Hong Kong.
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