82 



RECORD AND REDUCTION OF THE TIDES. 



nished to Prof. Bache by the Hydrographer to the Admiralty, Captain J. "Wash- 

 ington, E,. X., and are given in the appendix to this paper. And finally, 



Van Rensselaer Harbor, latitude 78° 37', longitude 70° 53'. High water at 

 F. & C. 11'" 50", as derived from the preceding analytical expression. Rise and 

 fall at spring tide 11.1 feet, at neap tide 4.7 feet, average range 7.9 feet. 



By means of the difference in the establishments of Holsteinborg and Van 

 Rensselaer, we ran obtain an approximation to the depth of Baffin's Bay and Smith's 

 Straits, viz: — 



Tidiil hour. Longitude. Sum. . Difference. 



Holsteinborpr 6" 30'" S"" 35° lO"" 05"" , I Difference corrected for the 



Vau Rensselaer 11 50 4 43 16 3?, { moon's motion 6" 26°. 



Assuming the distance along the channel to be 770 nautical miles, we have a 

 velocity of the tide wave of about 202 feet in a second, which, according to Airy's 

 table (174), Tides and Waves, would correspond to a depth of nearly 1300 feet, or 

 about 220 fathoms — a result probably smaller than the true value, since the other 

 observations indicate a greater depth, it may be taken as an inferior limit ; in the 

 same manner we find from the co tidal hours of Upernavik and Van Rensselaer a 

 depth of near 800 fethoms, and a similar result from the Wolstenholm observa- 

 tions ; this last result may perhaps he taken as an upper limit. 



Soundings. — The following soundings have been copied from the log-book: — 



Jime 19, 1853. I-at. 51^ 12', long. 52^^ 8' (government sounding twine and .32-pound shot). 



Chronometer time. Mark. 



8" 4T" 0' Red, started. 

 49 10 Wliite. 



52 10 IJottom, with 118 fathoms; shot brought up with graj' mnd 



and fine sand. The line was afterwards measured. 



June 26, 1853. Lat. 59° 48', long. 50° 3' (government sounding twine and 32-pound shot). 



Mark. Clironometer time 



Started 15 fathoms from tlie ne.xt mark. 4'' 21'" 25' 



Red. 25 



Wliite. 29 



Red. 33 



Blaclc. 31 



White. 42 



Red. 46 



White. 51 



Red. 56 



Missed tlie mark. 58 



August 1, 1838. Melville Ba_v, lat. 15° 40', long. 62° 12' (government sounding twine and 32 

 shot). 



