18 



The following is a summary of the ice and water temperature 

 reports received during the cruise: 



Number of bergs reported south of 48° 00' N 21 



Number of bergs reported south of 43° 00' N 



Number of ice reports received 55 



Number of water temperature reports received 811 



Number of vessels furnishing ice reports 27 



Number of vessels furnishing water temperature reports 120 



Number of vessels furnished special ice information 16 



Number of vessels reported for violation of track agreement 2 



Figure 6 shows the ice conditions and surface isotherms for the 

 sixth cruise. 



RADIO COMMUNICATIONS 



Radio is by far the most important equipment of the ice-patrol 

 vessels. It is only through the radio that the latest ice information can 

 be gathered and broadcast to shipping. Again radio is used to gather 

 surface water temperature reports from all vessels crossing the ice 

 regions. Therefore it is very necessary that the ice-patrol vessels 

 be equipped with the latest and best radio equipment obtainable and 

 have in their complement a group of well-trained and reliable radio 

 operators. 



Each vessel carried a chief radio man and four additional operators. 

 While some of the operators were new to the ice-patrol work and the 

 heavy radio traffic involved, they soon learned to operate the equip- 

 ment to the full extent of its capacity. 



Each vessel carried the following radio equipment : 



One S. R. A. 9 receiver for 25,000 to 1,200 kilocycles. This receiver 

 was used for the schedules with station NAA at Washington, D. C. 



One C. G. R. 25A receiver for 1,000 to 75 kilocycles. This receiver 

 was used during April to Hsten to vessels and shore stations. 



One C. G. R. 31 receiver for 550 to 90 kilocycles. This receiver was 

 used to listen to vessels on 500 and 425 kilocycles and to shore sta- 

 tions on 125 to 150 kilocycles. 



One C. G. R. 30 receiver for 2,705 to 2,355 Idlocycles. 



One T-4 200-watt transmitter. This transmitter was held in re- 

 serve as an auxiliary set and used each day to test for radio direction 

 finder bearings from Cape Race. 



One T-14 500 to 750-watt transmitter. This set was used in work- 

 ing vessels sending ice and water temperature reports and also for the 

 routine broadcasts. 



One T-17 300-watt crystal-controlled, high-frequency transmitter. 

 This transmitter was used to work NAA at Washington, D. C., on the 

 routine schedules and to work Coast Guard ships and stations. 



One radio compass. 



