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In New Zealand the influence of the land is far from being as important as in Australia, and westerly winds largely prevailing as on the sea in the same latitudes (36° to 47° S.). There is a difference between the east and the west coast of the south island, separated as they are by the high and steep chain of the New Zealand Alps.

PACIFIC OCEAN.

As in the case of the Indian Ocean, the materials for the study of the winds of the Pacific are the percentage of the winds, as collected by Prof. Coffin, selections from which are given in the following table:

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Zone 10. N. 403 and 404. Pacific Ocean, 1200

-1500 E.
14. Pacific Ocean, 1250-1400 W.
14.

120 -130 E.
14. N. 2. Sandwich Islands .
15. China Sea, 1060-1150 E.'
15. Pacific Ocean, 1350-1500 W.
16.

105 -115 W.
17.

90 -100 W. 17.

120 -130 E. 18.

155 -165 W. 19.

175 -180 W. 19.

145 -160 W. 19.

120 -125 W. 20.

100 -105 W. 21.

150 -155 W. 21.

175 -180 E. 21.

105 -110 E.
22.

150 -155 W.
22. N. 7. Society Islands
22. Pacific Ocean, 850-1250 W.
23.

120 -150 W.
23. N. 55. Port of France, New Caledonia
24. Pacific Oceau, 1650-1800 E.
24.

175 -180 W. 25.

85 -90 W.

120 -150 W. 25.

175 -180 E. 26.

160 -180 E. 26.

120 -165 W. 26.

120 -125 E. 27.

140 -150 E. 28.

100 -120 W. 28.

85 -90 W.

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46 49 2 0.4 0.8 0 0 3) 12 51 23 3 2 3 3 2

0 15 17 13 18 27 8 215 57 17 8 1 1 0 1 0.3 47 34

9 9 0.4 0.2 0.2 12 26 4 4 5 22 9 17 3 3 6 17 37 27 7 2 19 55 15 8

0 0 1 8 63 22 4 0.7 0.8 0.8 1 19 8 5 5 722 171 17 9 54 28 4 3 1 8 0.6 0 4 45 38 8 0 5 52 19 8) 13 3 0 0 8 6 9 29 24 7 13 8 62 22

5 0.5 0 3 0 14 43 35 9

0 2 16 41 37 5 0 0 5 24 42 22 4

3 0 25 24 13 16 3 2 6) 12 3 25 21 33 3 7 9 16 68 3 4 3 3 3 0 4 46 44 6

0 0 0 0.3 26 59 15 0 0 0 0 16 70 11

0 1 11 84 4 0 0 047 32 20 0 0 0 11 51 30 3 0 11 3 1 2 45 43 5 0 4 0 5 22 20 20 11 8 6 8 4 7 47 30 8 2 0.3 0.3 4 1 5 12 26 27 21 5 6 8 30 39 3 8 3 10 35 29 12

10.5

61 6 2 13 27 14 12 17 8 8 7 24 31 2 0 1 14 21 1 5 24143 14 1 3 3 3 5 34 5061 0101 16 28 11 9 7 3 8 19 10 22 38 17 3 1 3 5 1 0 18 54 3 4 12 8 0 0.2 5 79 13 2 1 0 8 14 17 13 13 14 16 4 4 11 40 18 6 5 13 24 16 8 19 11 4 8 29 35 10 8 4 2 13 13 8 14 5 15 12 20 2 51 16 30 12 11 15 10 C- 34 1 3 1 15 21 31 22 12 11 14 9 11 10 11

6 14 23 15 6/25 3 7 4 12 33 19 11 7 12 3 17| 12 4 14 81 16 11 18|| 16 14 11 8) 13 14 10 14 25 8 7 13 7 13 10 161 11 10 16 13 7 13 17 12 16 3 2 0 11 11 28 30 12 9 13 8 13 20 18 8 11 7 4 7 16 16 19 19|| 11 8 8 5 8) 131 27 19 13 7 0 12 14 12 34 6 7 5 5 3 5 23 35 15 11 5 4 7 22 22 15 14| 10 2 2 1

6 19 36 23

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What distinguishes the Pacific Ocean from the Atlantic is a less regular S. E. trade, which seems to be caused by the numerous islands of Polynesia. Many of them are high, volcanic, so as to intercept the wind for a certain distance. Another influence exerted by these islands is the local rains, which are produced by them, partly by condensation of the vapor brought by the trade; partly due to local calms and the ascending current. These condensations of vapor cause a lower pressure, and the movement of the surrounding air to supply the deficiency causes irregular winds.

For the whole year.

Especially in the central and western part of the ocean (between 10°—20° S.), are these irregularities noted. It will be seen that in these parallels the S. F. trade is very regular in the Atlantic Ocean. (Plates 5 and 6.)

The inner boundaries of the S. E. and N. E. trade are given as follows by Kerhallet in his “ Considerations Générales sur l'Ocean Pacifique.”

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These observations show that the belt of equatorial calms is always north of the equator. It seems that the figures given by Kerhallet are taken from observations in the eastern part of the ocean, near the American coast, where really the S. E. trade crosses the equator. The wide limits between the two trades in summer are caused by the prevalence of the S. W. monsoon on the coasts of Central and South America. (See Plates 5, 6 and 7.)

In other parts of the Pacific Ocean the equatorial calms seem to be nearer to the equator, and partly even south of it. According to the statements of numerous navigators the trades are also more easterly there, and often do not leave any calmbelt between them, so that a ship can sail from the one into the other trade without interruption, as was also stated for the western part of the Atlantic Ocean.

The northern limit of the N. E. trade is also in a comparatively low latitude in these parts, as shown, for example, by the observations at the Sandwich Islands. They seem to be already in the zone of variable winds in the winter, N. E, and S. W., the one being noticed about as frequently as the other. Rains are also frequent in this season, with S. W. winds, thus corroborating the testimony of the wind observations,

The system of winds along the western coast of America has been already discussed.

As to the middle latitudes of the southern hemisphere in the Pacific, the same may be said of them as of the same latitudes of the Atlantic, and Indian Oceans.

ANTARCTIC ZONE.

I give next some calculations from the extreme southern part of the Pacific and Antarctic Oceans, comprising the most southerly latitudes to which man has yet penetrated.

See Pilot Chart of Atlantic, Pacific and Indian Ocean, edited by the British Admiralty. Unfortunately I could not obtain it in Washington, and thus have not the possibility of tracing the limits of the trades and monsoons according to the best source, as in the Atlantic.

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6 9 11 8 10 16 26 13

7 10 10 10 13 19 16 15 28 5 4 0 4 4 39 14 11 3 3 17 6 17 25 17 11 7! 5 2 11 33 18 13

8 8 22 0 1 11 33 16 14 13 12 5 18 18 9 12 6 6 0 2 10 29 47 8 4 3 6 15 21 27 16

Zone 29. 1600-165° W.

29. 80 -85 W.
29. N. 51, Heard's Island
29.

N. 28. 60°-70° W.
29.

N. 13. Off Cape Horn
30. 85°-115o W.
30.

56 -58 S., 750-79° W.
30. 56 -58 S., 69 -71 W.
30. 56 -58 S., 65 -67 W.
31. 60 -62 S., 63 -83 W.
31. 60 -65 S., 5 -15 W.
31. 60 -65 130 -135 E.

60 -65 160 -176 E. 32.

105 -160 E.
32.

160 -176 E.
33. By Sir James Ross
34. By Sir James Ross

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19 10 6 4 6 13 19 22 13 3 1 2 7 18 29 26 24 2 9 1 3 6 38 18 17 6 3 2 8 26 22 15 11 4

3 8 20 31 21 13 3

5 10 29 30 8 4

4 3 16 30 33 8 5 1 7 19 35 23 10 5 1 1 6 22 38 16 7

0 0

2 43 43 11 12 15 16 19 13 85

045 28 13 5 6 3

4 11 11 0 14 31 26 2 2 18 22 21 20 12 4 11 13 16 9 12 18 10 10 5

9 20 28 8 16 9/5 6 19 24 15 12 78

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The observations in these high southern latitudes are very conclusive; from the zone of the most prevailing westerly winds between 50° and 60°, we pass to a region of southerly and easterly winds further south. The latitudes at which these winds become prevailing are not the same in the whole Antarctic Ocean. South of Cape Horn W. and N. W. winds largely prevail between 60° and 62° S., and further south there are no observations in these meridians. Southeasterly winds are already prevailing in the meridians of the Atlantic Ocean, between 60° and 65° S., and also south of Australia, while again on the meridian of New Zealand 160° to 176° E., westerly winds are the most frequent. This seems to depend much on the currents of the sea. Where warm currents carry a high temperature further south, pressure will be lower there than in the same latitudes generally, and westerly winds will also extend further southward. Between 65o and 70° S. Lat., on the meridian of New Zealand, there is already a slight prevalence of southerly winds.

Between 70° and 78° S. the observations of Sir James Ross show this to be largely

the case.

Thus the hypothesis of Prof. Coffin as to the prevalence of polar winds (S. and E.) is shown to hold good also for the southern hemisphere, notwithstanding the small number of observations we possess from high southern latitudes. As to the division-line from the W. and N. W. winds of the temperate regions, it cannot yet be traced with precision.

DESCRIPTION OF MAPS AND DIAGRAMS.

The direction of the wind on the maps, Plates 1 to 13, is indicated by arrows. For example, to indicate a N. wind, the head of the arrow is turned towards the south, and the tail towards the north. The direction indicated is not that of the prevailing wind, but the mean direction, the manner of calculation of which was explained in the beginning of this work. The length of the stem of the arrow, exclusive of its barb, is proportionate to the ratio of resultant, the greatest length being when the ratio is equal to 100, or when all winds come from the same direction. These maps weré originally all drawn to a scale, in which one hundred per cent., as found in the tables, was intended to be represented by an arrow an inch in length; but, by the process of engraving adopted, it was found practicable to diminish the size of the maps somewhat, so that 100 per cent. equals two-thirds of an inch ; for instance, on Plate 1, Zone 10, serial number 196, representing Eastern Pennsylvania, the arrow is 20 one-hundredths of an inch in length, corresponding to the tabular percentage .30 given on page 320. The more equally the winds are distributed around the horizon the smaller is the ratio, and also the shorter the arrow on the map. Where it is very small it indicates that there is no really prevailing wind. This is generally found on the boundaries of two systems of winds.

PLATE 1.

ANNUAL DIRECTION OF UPPER AND LOWER CURRENT IN THE UNITED STATES.

The mean direction of the wind, as observed by the wind-vane, is indicated by full arrows, and the direction of the motion of clouds by broken arrows. It will be seen that they very nearly coincide in nearly all regions of the United States. Generally the upper current is more purely west in all the regions east of the Mississippi, while the lower current has a more W. S. W. direction between the Mississippi and A pallachian Chain, as well as in the Southern Atlantic States, while in New England the winds are rather W. N. W. Near the Gulf of Mexico the arrows have a very different direction, but it will be seen that the arrows are very small, thus indicating an undecided prevalence of any wind.

In some parts of Texas, also, the upper and lower current seem to come from different directions. In this map, as well as in the others, the figures relate to the serial number in the zone, and, by reference to the Numerical Index to Stations, given on pages 52 to 66, it is easy to find the name of the place indicated by each figure.

PLATE 2.

MEAN ANNUAL DIRECTION IN THE ARCTIC REGIONS.

It will be noticed that the mean direction of the wind is from the north in Greenland and Arctic America, and that the arrows are long, thus indicating very prevailing winds. On the northern coasts of Europe and Asia the winds are from the south, while Bear Island, between Norway and Spitzbergen, as well as Iceland, have prevailing easterly (polar) winds. In this map a dotted line is traced, and called “Southern limit of polar system.” This is the same boundary as that traced by

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the late Prof. Coffin on the maps of the “Winds of the Northern Hemisphere.” In the mind of the deceased author this was the boundary between the prevailing polar winds of the Arctic regions and the equatorial (westerly) winds of the middle latitudes of the Northern Hemisphere. He traced it at a distance of 28° 20' from an imaginary point which he called the “Meteorological Pole," and located in 84° N. lat. and 105° W. long.

PLATE 3.

MEAN ANNUAL DIRECTION BETWEEN 80° N. LAT. AND 56° S. LAT.

arrows.

The general prevalence of westerly winds will be seen here in the middle latitudes of the Northern Hemisphere. Yet they are not always true equatorial winds, but incline somewhat to the north in some regions. On the tropical seas easterly winds largely prevail, as indicated by the length of the

This is the region of the trade-winds which prevail more largely in the Southern Hemisphere than in the Northern. In the middle latitudes of the Southern Hemisphere westerly winds again prevail, and this to a large extent, while further south there are again easterly (polar) winds. In some parts of the globe, where monsoon winds prevail, the length of the arrow showing the meani annual direction is rather small (as in India, China, Japan). This does not come from an undecided character of the winds, but is caused by the nearly opposite direction of the winds in winter and summer. As they counteract one another in the yearly resultant, the ratio of the latter is small. A reference to Plates 5 and 6, giving the mean direction of the wind in summer and winter, shows that at each season the arrows in China, India, Japan, and the surrounding seas, have a great length, showing largely prevailing winds at both seasons.

Monsoon comes from the Arabic word Mausim, or wind of the season. We call monsoon regions those that have winds of nearly opposite character in winter and summer, each of these winds prevailing during some month of the year nearly to the exclusion of all others. On the greatest scale we see such winds along all the southern and eastern coast of Asia, and on the surrounding seas, the winds in the tropical part of this country being N. E. in winter and S. W. in summer, while further north, in the interior of India, China, Japan, and the Russian Amoor provinces, the winds are rather N. and N. W. in winter, and S. and S. E. in summer. Monsoon winds are caused by the mutual reaction of great continental masses and the ocean, and thus they are most prevailing where the greatest continent- Asia-approaches the greatest oceans—the Pacific and Indian. winter the pressure of the air is high on great continents, and thus air flows out from there, while in summer, on the contrary, the land-masses being highly heated, an ascending current is produced and the air from the surrounding oceans is drawn in to supply the deficiency. In all parts of the earth, where continents and oceans adjoin, we see a tendency to produce monsoons. This is what Prof. Coffin has called monsoon influences, but not everywhere monsoon winds are dominant. Monsoon influences may be considered as small deflections from the mean annual direction in regions where no great differences in the mean direction of the wind in the different seasons are experienced, and thus this relative influence of land and sea is small. In monsoon regions, on the contrary, this influence is experienced on the largest scale.

PLATE 4.

MEAN DIRECTION IN THE FOUR SEASONS IN TIIE ANTARCTIC REGION.

The direction of the wind is here represented by broken arrows, thus:

A straight line drawn from the tail to the head of the arrow gives the mean annual direction. The sequence is always—spring, summer, autumn, winter. Thus the nearest part to the tail of the arrow indicates the mean direction and ratio of resultant in the spring, and the nearest to the head that of winter. As before stated, June, July and August are denominated "summer," etc.

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