288 THE VOYAGE OF THE JEANNETTE. 



the prismatic colors in modified tints crossed and re- 

 crossed each other, while the whole looked like a mag- 

 nificent pyrotechnic display on which various colors and 

 intense lights were thrown. 



'• In the W. th'e band showed occasionally that at a 

 great distance in that direction similar movement was 

 in progress, while to the eastward such a movement 

 was plainly discernible, the rapid changes of the fold- 

 ings in the band taking the forms of spiral curtains. 

 The whole display, after lasting a half hour, moved to 

 northward of zenith, fading as it went." 



In my remarks on the 14th December, I mentioned 

 our experience in reference to a statement of Wey- 

 precht, that " beginning at a certain thickness the ice 

 is almost free from salt." Besides testing the ice six- 

 teen inches thick, we have since tested ice four feet 

 thick, and found it full of salt. Evidently we have not 

 reached that " certain thickness." 



In Dr. Kane's narrative of the De Haven Expedition 

 he makes the following statements : " By the time we 

 had reached the middle of Barrow Strait, and the win- 

 ter's midnight of December had darkened around us, 

 our thermometer indicating a mean of 15° and 20° be- 

 low zero, the ice attained a thickness of three feet, with 

 an almost flinty hardness, and a splintering fracture at 

 right angles to its horizontal plane. Such ice was at its 

 surface completely fresh, and when tested with nitrate 

 of silver gave not the slightest discoloration." To ques- 

 tion such an authority as Dr. Kane is considered to have 

 been is a somewhat rash undertaking for me, but I as- 

 sert that we have tried all thicknesses of ice, from surface 

 efflorescence to floe pieces eight feet in thickness (which 

 had been up-ended in pressures), and have never found 

 any which would upon melting give potable water. If 



