51 



mental ones, cletermined months previously in the Arctic regions. 

 The variations are intensified or ameliorated by* meteorologic and 

 hydrograpliic forces as they react over this time and space. 



With only three days of good visibility during this entire cruise, it 

 was not possible to make a comprehensive, thorough search. Of the 

 11 bergs sighted, probably not more than two remained as a potential 

 menace to the steamer lanes at the end of the patrol period, and it is 

 believed they are north of lat. 42° 30'. Ice warnings were broadcast 

 twice daily on 600-meter and once daily on 2,300-meter wave lengths. 

 A daily ice report was sent to the Hydrograpliic Office and a morning 

 and evening weather report to the Weather Bureau, Washington; 

 236 vessels furnished the patrol with 1,112 water temperature reports 

 and 26 vessels reported ice; special ice information was furnished to 

 19 vessels and 6 were warned. 



COAST GUARD CUTTER "TAMPA," LIEUT. COMMANDER W. J. WHEELER, 

 ICE PATROL, FOURTH CRUISE, JUNE 16 TO JULY 2, 1923. 



The Tampa sailed from Halifax at 11.10 a. m., June 14, to relieve 

 the Modoc on ice patrol. Light to moderate NNE. to SSE. breezes 

 were experienced during the trip, with fog at intervals on the 15th. 



June 16: Contact was made with the Modoc at 6.45 p. m., in lat. 

 42° 48', long. 53° 15'. The oceanographic observer was transferred 

 to the Tampa, which then took over the ice patrol, the Modoc pro- 

 ceeding to Halifax. At 7.35 p. m. stood a course for lat. 42° 00', 

 long. 51° 30', to commence search from that position at daybreak 

 next morning to long. 50° 20', thence to northward. 



The following summary of the ice situation was made by the oceano- 

 graphic observer: During the past two weeks there have been only 

 two days on which it was not foggy. June 9 a total of eight bergs 

 were found bunched in deep water off the Tail of the Bank. They 

 were drifting vSW. at the rate of 0.4 knot per hour, in the axis of the 

 Labrador Current. Since then they have not been sighted south 

 of the fog line (parallel 42° N.), therefore it is believed that they 

 have been set in on the SW. slope of the Bank. There are two bergs 

 to the W. and NW. of the Tail, which will probably disintegrate there. 

 The Arctic Current has increased during the past two weeks and is 

 now in large volume around the Tail and extending to the southward. 



June 17: Moderate to gentle SSW. breezes in forenoon, falling to 

 light S. airs in afternoon. Vessel on course to arrive at starting 

 point of search by daybreak. At 4.15 a. m., fog shutting in, stopped 

 and drifted. At 5.45 a. m., fog clearing, proceeded on course. At 

 7.35 a.m., fog again shutting in, stopped and drifted. At 8.10 a.m., fog 

 clearing, again stood on course, until again in fog at 8.55 a. m. Stood 

 S. until clear of fog, at 10.15 a. m., then E. until again in fog at 



