172 



The observations on the wind were made three times a day : — 9 a. m., 

 1 p. M., 5 p. M., — and represent the magnetic direction of the wind in the 

 Bay, as taken from the direction of the ships and their flags with a ship's 

 compass. 



I have received, through the Rev. Professor Haughton, the follow- 

 ing information from the Eev. Dr. Lloyd, as to the variation of the com- 

 pass at Simon's Bay : — 



"Simon's Bay is aboat thirty miles from Cape-Town, and nearly 

 due south. The isogonal lines make a curious bend all along the west 

 coast of Africa, thus — 



From Sabine's map for 1840, there appears to be an increase of F of 

 Declination for 4' increase of S. Latitude. Hence it would follow that 

 the West Declination at Simon's Bay is 6^ minutes greater than at Cape- 

 Town. 



^' The magnetic declination at Cape-Town, corresponding to the 

 epoch September 1st, 1848, was 29° 14'.6west. The mean change from 

 year to year is, at present, + 0^5 ; but it appears to be increasing." 



From this statement it follows that, as the magnetic declination is 

 diminishing, in 1860, the declination was at Simon's Bay 29° 15' W. 



I have given in Table II. both the direction and force of the wind ; 

 the latter estimated as miles per hour, according to Beaufort's scale, as 

 well as I was able to apply it ; and in Table III. I have given the 

 direction and force of the wind referred to the 32 points of the magnetic 

 compass, from which Table may be calculated the resultant frequency 

 of wind, and the resultant wind of each month. 



AFRICA 



