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ANNUAL REPORT SMITHSONIAN INSTITUTION, 1912. 



In the long iceberg you can see the dangerous overhanging ridge, which is caused 

 by the underwater melting, and the lapping of the warmer water waves against the ice. 

 This ridge is always found on bergs which have not recently turned over. 



In the records which Mr. King was able to get for me in 1910, besides the rise of 

 temperature a fall of temperature was obtained when the ship approached the various 

 icebergs with the exception of one. These bergs were all floating in the main Arctic 

 current off the eastern coast of Labrador. In the light of my recent work I feel sure 

 that the drop in temperature was due to the influence of the cold current in which the 



iceberg was floating. These cold currents exist in the main Arctic current whether 

 ice is present or not, but the presence of the ice is to slightly elevate the temperature. 

 To assist in illustration of my meaning please refer to the microthermogram taken on 

 the Allan Line R. M.S. Victorian last June (fig. 11). This record, which is a direct tiuce 

 from the chart on the instrument, is through the ice track at a depth of 18 feet, by the 

 Cape Race route. After passing the ' ' Cold wall " the Arctic ciurent drops in tempera- 

 ture regularly as the ship proceeds westward. The small variations up and down are 

 partly due to icebergs passed at distances of 6 to 8 miles, and partly due to colder 



