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PLATE 26.

DEFLECTING FORCES,

The “S-shaped” curves

are divided into twelve parts to denote the path traversed by a particle of air, in each of the months of the year, when subjected to the winds that are found at Amherst, Massachusetts, Easton, Pennsylvania, New York City, Paris and Pekin, which are taken as representative places. In each case is seen the "parallelogram of forces," of which the diagonal represents the monthly resultant, one side one-twelfth of the yearly resultant, and another side the monsoon influence. Near each is gathered a parallel series of arrows to show the position of these monsoon influences relative to each other.

The law of the Monsoon Influences is seen in two facts: 1st. All these places, except Paris, are situated on the western shore of the adjacent oceans, and their monsoon influences are from the southsoutheast in summer, and from the north-northwest in winter; but at Paris, not thus situated, their direction is reversed. And 2d. The monsoon influences at Pekin, which is emphatically in the monsoon region, and at New York, which is near the ocean, are greater than those at the other places which are not thus situated.

In the diagram at the right, in this Plate, representing an aggregate period of 560 years of observation, taken at more than 60 places in the State of New York, the approximate parallelism and equality of the arrows show the permanent character of the winds, and their divergence or inequality their annual mutations; yet the latter are rather apparent than real, since they are due chiefly to the introduction of new stations or discontinuance of old stations, so producing a slight modification of the result, and not indicating any really marked differences in the annual resultants. Two striking instances of diurnal variation in the direction of the wind are given on the lower part of the Plate for Hudson, Ohio, and St. Petersburg, which are easily explained by the proximity of each of these places to a considerable body of water situated north and northwest of them.

SOUTHERN IMITADY POLAR SYSTEM 7150 North Latitude

Ulea

Sold Aland Islands 80° North Latitude

PLATE 2. 180

120

110
East 100 Longitude
90 from
Greenwich. 70

60

50 Nasimowo

Zlatousto (Bache Aktolik

ctia Nertchinek

Nino Tagulat

Kazan

Bogoalomik bi
140
SI BER

Novogoro
A

Viatks

Vladimir
Yakoutsk
Anginak

Kostroms Moscow
Lake Plasana

Totma
Yarenak

Vologdao os

RU

S SI A 155 Okotek Okotsk

30

Archangel
Eorgnnego Filipooskoge b Taimurlend

Ligatel

Onega

St. Petersburg JPRE SEA

Dorpat
Nouembla

Kem
Hogeland

Riga
Uat Yangka

FINLAND Laked

elastfors

Kajan Petronatulala 160

Palviamo

Bio

Remo Genset
Vardo
North Cape

Mites
Et

Ups
Carenja
Lammer

fiefhe Nifne Kumsk

locum Hermosen Fahlan Tromsoe Stengele

Ostersund
Baranon Rock

NORWAY
Bear Islands

Dear and

Drontheim

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