24 



THE NINTH CRUISE, " TAMPA," AUGUST 2-4 



Upon relieving the patrol on August 2 the Tampa instituted a 

 final search for the southernmost ice. By 10 a. m. the southern end 

 of the cold current with surface temperatures between 55° and 58° F. 

 just southeast of the Tail was entered. It was found to be but 20 

 miles wide, being bounded on the west, south, and east by water 60° 

 and higher in temperature. Good visibility prevailed until the search 

 had been carried north along the eastern edge of the Banks to 43° 

 30' N. Here 52° water covered with a low fog w^as met. At 7 p. m. 

 on the 2d the Tampa was stopped for the night in 43° 42' N., 49° 05' W. 



The Modoc had watched all the bergs south of the forty-third 

 parallel break up during the previous cruise, and only two other 

 bergs south of the forty-eighth parallel had been reported since 

 July 22. The more southern of these was in 44° 52' N., 48° 34' W., 

 on July 27. When no ice was found in the cold water south of 43° 

 30' N. by the patrol it became evident that this berg had either 

 melted or drifted off to the northeast. It seemed a practical certainty 

 that the ice menace for the 1929 season was absolutely over so far as 

 the "B" tracks were concerned, and fairly certain that no more bergs 

 could get south of the forty-third parallel before the spring of 1930. 

 Accordingly, a message summarizing the situation and recommending 

 the discontinuance of patrol was transmitted to headquarters on the 

 evening of August 2. 



On the 3d a southwesterly course was run across the Tail. Fine 

 visibility prevailed over the shoal w^ater, which was warmed to from 

 60° to 64° at the surface, but fog continued over the cold stream off 

 the eastern edge. On the afternoon of the 3d, when information was 

 received that the 1929 international ice patrol w^as discontinued, a 

 course was laid for Boston, Mass. The last broadcasts of the season 

 were transmitted on the evening of the 3d and on the morning of the 

 4th. They contained a notice of appreciation for the valuable assist- 

 ance in the way of reports received from shipping. Port was reached 

 without incident, and the Tampa moored at the Boston Navy Yard 

 at noon on August 6, 1929, thus ending the longest ice-patrol season 

 on record. 



One oceanographic station was occupied during the ninth cruise. 

 The water from it and from the 10 stations last taken on the Modoc 

 was run through the salinometer before noon on the 4th and all stations 

 were computed before Boston was reached. The isotherms on the 

 cruise chart for the short ninth cruise are based on 148 values sent in 

 by 16 different vessels and on 102 readings taken irom the log of the 

 Tampa. The curves show some continuation of warming in the sur- 

 face layers. There was only one ice report received; one vessel given 

 special ice information. 



