Hydrographical Observations from the Danmark Expedition. 417 



these instruments were let down into different depths. Further, some 

 large cylinders (petroleum barrels without bottom) were suspended in the 

 depths 100 m. and 200 m. by means of thin piano wire, so that the 

 influence of the current on this wire might practically be excluded; 

 the movements of the cylinder would thus be an indication of both 

 the direction and strength of the current in the respective depths. 



It was found in this way, that the rapidity of the current was 

 as a rule greatest at a depth of 20 meters below the surface and least 

 at the surface and near the bottom, probably as a result of friction, 

 on the one hand against the ice and on the other against the bottom, 

 as also that the current ran as a rule in the same direction throughout 

 the whole layer from surface to bottom and likewise changed simul- 

 taneously; but sometimes the current ran in in the deepest layers, 

 whilst running out at the surface, and waves could thus arise. 



Table 12 shows the result of these simultaneous measurements. 



Tidal observations. 



Continuous series of tidal observations were made in Danmarks 

 Havn in both уЛтЛет half-years 1906—07 and 1907—08 by First- 

 lieut. Bistrup. In addition to these, a number of tidal observations 

 were made by myself on the outer coast at Maroussia in the spring 

 of 1908 and also ca. 70 km. further west in one of the inner fjords 

 (Mørkefjord) in the neighbourhood of the inland ice. 



The measurements were carried out by means of a divided, wooden 

 rod wdth a piece of iron at the lower end; through a hole in the ice 

 this was made fast to a stone on the bottom in the neighbourhood 

 of land where the depth was ca. 3 m. 



1. Tidal observations at Maroussia. (Table 13 p. 418 — 20.) 



Remarks: The observations were made between .SO/vi 08 and 

 6/vii 08 and gave as result, that the difference in the height of the 

 tidal wave varied during these days between 111 cm. and 81 cm. The 

 tidal period*) varied between 10 hours 38 minutes and 9 hours 39 

 minutes and was thus on an average 10 hours 6 minutes. 



The moon was new moon on 28/vi and in its first quarter on 6/vir. 

 Highwater in the day-time during this period was higher than night 

 highwater, as the follo%ving Table shows: 



Day highwater Night highwater 



1/vii 12.33 p. m. height of water 194 em. 30/vi 12 midnight, height 182 cm. 

 3/vii 1.40 — — - — 202 - 3/vii 12.45 a. m. height 189 cm. 



4/vii 2.16 — — - — 195 - 5/vn 2 a. m. height 171 cm. 



•"I Tidal period see: foot-note Table 11 p. 415. 

 XT.i. 27 



