SCIENTIFIC RESULTS 161 



in«:" the years 192G and 1927 the circulation of the water masses in t[ie 

 iceberg re<rion south of Newfoundland w^as kept constantly under 

 surveillance by means of frequent current surveys covering areas 

 of several thousand square miles. The general results have been 

 discussed in earlier pul»lications (Smith 1927 and 1927b). to which 

 are referred any students interested in the details of the circulation 

 in special regions. 



In general the agreement between the berg tracks that have ac- 

 tually been followed (figs 103, 104,105, and 106) and the gradient 

 currents for the same periods, respectively (overlays for figs. 103, 

 104, 105. and 10(5 ). is so close as to indicate that dynamic projections 

 of tliis sort may l)e used as a basis for predicting the tracks that 

 individual icebergs are most likely to follow (see p. 176). 



Occasionally icebergs survive relatively long periods, even when 

 floating in Atlantic Ocean water of high temperature, and they 

 may then make phenomenal journeys. Thus icebergs have been 

 sighted near the Azores, near the British Isles, and even near Ber- 

 muda, such events usually taking place late in the season and during 

 bad ice years such as 1890 and 1912. These drifts, however, do not 

 indicate a direct extension of the Labrador current into low lati- 

 tudes but simply that the bergs in question have been caught up in 

 oceanic vortices tliat are continually forming over the Atlantic basin 

 in which the ice is borne southward instead of following the normal 

 drift.'"' The emphasis that has often been laid on bergs drifting 

 exceptionally far southward is apt to give an exaggerated impression 

 of the frequency of such events. As a matter of fact, it is unusual 

 for a berg to drift south of the fortieth parallel of latitude in the 

 western North Atlantic, the records for the past 20 years showing 

 only one such occurrence every one to three years. 



Tlie Deutsche Seewarte (1902, tafel 3) published a map showing 

 the positions in which shi))s have reported ice far south in the At- 

 lantic. During May and June of the year 1890 some bergs attained 

 the thirty-seventh meridian between latitude 44° 30' and 46° N. 

 During the period 1904-1913 ice was sighted at least once south to 

 latitude 37' 50' north and east to longitude 38° ; with one exceptional 

 journey to the thirtieth parallel. In May, 1905, a few bergs pene- 

 trated "the Atlantic to latitude 39° 07' directly south of the Grand 

 Bank. In 1912. the year tlie Titanic was lost, a berg reached lati- 

 tude 39'. longitude 47°. 



Hennessy (1929. p. 84) has published a list of extraordinary berg 

 drifts which shows that only 24 bergs during the past 20 years have 

 been sighted south of the fortieth parallel. 



Some of the ]:>ositions in which ice has been reported seem hardly 

 credible — due to errors in observation or in transmitting radio re- 

 ports — had they not been verified. One of the most astonishing inci- 

 dents is the rei)ort made by the British steamer Baxtergate and 

 verified l»y the I'nited States Hydrogra])hic Office that on June 5, 

 1926. she passed a large j^iece of ice 30 feet long. 15 feet wide, and 3 

 feet above water in the latitude 30° 20' N., longitude 62° 32' W., near 

 Bermuda. Such an occurrence is the more mysterious when it is 



" It has already liepii pointed out that the outlet for icelwrgs dopaiting on extrasoutherly 

 drifts is noticeably conrined between meridians 46 and 50, almost directly south of the 

 «;rand Hank. (Smitli. 1927, p. 68.) 



