THE WEDDELL QUADRANT AND ADJACENT AREAS. 115 



consideration the isobars west of the 65th meridian (and probably farther west) lay- 

 approximately north and south, with pressure as high over Graham's Land and Cape 

 Horn as at the Falklands (see Plate IV. fig. 4). At the South Orkneys, pressure, 

 although above the average, was 0'30 inch lower than at Charcot's Winter Quarters, 

 indicating a still lower barometer to the east. The prevailing winds over a very wide 

 area south of 50° S. on the Pacific and 40° on the Atlantic side were from the south or 

 south-west. That these were also the prevalent winds between the South Shetlands 

 and the South Orkneys is evident by the low latitude in which the Argentine corvette 

 " Uruguay," on her voyage to the South Orkneys in 1904, met with the pack, this 

 being encountered in lat. 58° 40', long. 50° 40' W. The vessel arrived at the South 

 Orkneys on 31st December, having forced her way through 250 miles of ice. On her 

 voyage to Gerlache Straits I had an opportunity of examining the pack. I perceived 

 that it showed hardly a trace of having been subjected to oceanic swell, while the 

 presence of unbroken ice fields as much as 30 miles in length, not far removed from the 

 outer edge of the main body, in lat. 59° 5', long. 49° to 50° W., was further proof of the 

 absence of the normally prevailing westerly and north-westerly winds. I have referred 

 to these facts as they bear directly on the question of the prevailing winds over the 

 region and the trend of the isobars. That unusually quiet weather prevailed to the 

 west of 65° W. and at Cape Horn is indicated by the total absence of strong winds at 

 Dungeness and Evangelists Island, while the comparative rarity of gales at Charcot's 

 Winter Quarters is also worthy of notice. At the South Orkneys, however, south-west 

 gales were frequent, especially after the middle of the month. On the mainland of 

 South America the most pronounced feature was the persistence of a low-pressure area 

 oft" the coast of Chili in about lat. 40° S. This type of pressure-distribution prevailed on 

 nineteen days of the month, but on the chart for the whole month the more distinctive 

 features are masked by the normal conditions prevailing during the remainder of the 

 month. This is the type of pressure-distribution associated with the presence of an 

 Antarctic high at all seasons, and these highs appear to pass away to the N.E. and 

 over the Atlantic. In the table on the following page are given values of the 

 principal climatic elements for ten stations south of 40° S., and, as far as the data 

 permit, they have been compared with the normal. 



It will be observed that at Charcot's Winter Quarters temperature was about the 

 normal for the region, but that at the South Orkneys and at the island and coastal 

 stations on the east side of the southern extremity of the American continent it was 

 markedly below the normal, the deficit being practically the same, viz. 2°. On the 

 other hand, it was markedly above the normal at Ushuaia, the excess increasing in 

 a N.W. direction, and reaching 27° at Evangelists Island, where rainfall, cloud, and 

 wind-force were all much below the average. This result is obviously due to the 

 relative infrequency of the normal cool, onshore, rain-bearing winds, and the excess 

 of land winds resulting from the abnormal distribution of pressure referred to. It will 

 be observed that while southerly winds were in excess at the South Orkneys, a relatively 



