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1871] 67 [Chase. 
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PLOT dias suse hei Won daar 9 25 10 
DAUD AN igs os boot es wm ccgene 10 8 8 20 ABE 13 14 16 
Miss ll 1 9 15 12 15 10 17 
MHOUISIOMIE Sh ec eek ee 1S 220 iby lb 2 2 
LOMAS Cots TEA 23 5 6 16 81 8 5 6 
Tennessee .......... esd 7 ah 12 6.511 19 14 7 14 
ESGUUO CRY cis so sn ives < cad wren 6 3 4 7 Rial 3 14 15 
Oo ee ee 6 10 4 12 9 27 14 18 
MINCIIO AN « qseas a see 6 10 8 10 i) 22 18 16 
CIA Sitar eeciie ta. . 9 o 2g 12 3 19 a7 16 
Dinos nuiniinwii6 ww Bhs 6 12 6 12 14 20 14 16 
WM SSO0 ai ccs tec 8 8 107 219. lh aly 11 
MWUSCOUMID ici c ec help (Oe el abil 19 ig «1G 
lOWa se ee ge 10 5 a6 11 18 9 23 
Minnesota. ais eee 10 Oe D0 9 aby 8 14 23 
Nebraska: o).<6053 55> ints ok 9 5 2 25 8 6 14 
HANSA Ds pc koeete den veh 19 9 HA 14 26 dey 3 11 
WECM GOL bays sono vo on «ce 16 7 oe iL 6 6 3 8 12 
California Ae Gae 3) 3 3 14 alg) 18 ats) 3 8. 56 53 W. 
mociiease 0" ois sae sy 8 a7 12 14 10 20 10 S) ** 23 53. E. 
Giiatemalaccy. cies nce d 56x06 2 1 Oy 221 u 4 Me 
SURNAM secs as eck et es 5 41 22 22 ve 2 0 1 260; 58.¢5 
This grouping, by exhibiting the excess or deficiency, in the percent- 
age of any given wind, from the percentage of the same wind in adja- 
cent districts, shows local irregularities which are often easily explicable 
by the physical features of the neighborhood, and enables us, by plotting 
the general resultants on a map, to demonstrate the anti-cyclonic motion 
of the air, over the entire region between the twenty-fifth and forty-fifth 
parallel of latitude, and between Passamaquoddy Bay on the east, and 
the 100th meridian on the west. It shows, moreover, that there is a nor- 
mal intersection of a polar (N. E.) current off the coast of Florida, with 
an equatorial (S. W.) current from the Bahama Islands, and a similar in- 
tersection of a south-easterly and south-westerly equatorial current, (the 
latter having been refrigerated by the Sierra Nevada,) near the common 
boundary line of Nebraska and Kansas. The former of these intersec- 
tions is analogous to the one referred to by Mr. Scott, as indicative of an 
approaching gale in the British Islands, and suggests an obvious explana- 
tion of the gulf stream cyclones, as well as of the cyclonic winds in 
Western Europe; the latter helps to account for a considerable propor- 
tion of our land storms. 
The comparisun of these currents and intersections with Blodget’s 
hyetal charts is very instructive, and I feel little hesitation in predicting 
that a more thorough acquaintance with the winds of Alaska and British 
America, will develop another anti-cyclonic system, referable to a differ- 
ent centre of disturbance, with intersecting normals near the northern 
boundary line between the polar and equatorial prevailing winds, and 
perhaps in the valley of the Saskatchewan, which has been specially de- 
signated by Professor Henry as a storm-breeding district. 
