Astronomical Society. 459 



" Mars (near three o'clock). — The contrast of light in the vicinity 

 of the poles very decided j on the 3rd, several spots on his body, well 

 and strongly marked. This morning, that about the south pole 

 seems to overtake the body of the planet, and gives an appearance 

 not unlike that afforded by the new moon, familiarly known as ' the 

 old moon in the new moon's arms.' 



" Satimihsis been seen repeatedly with powers 130 to 928, under 

 circumstances the most favourable ; but not anything anomalous 

 about the planet or its ring could even be suspected." 



June 1 1. — The following communications were read : 



I. Observations and remarks made on a passage from New 

 South Wales to England, by Charles Rumker, Esq., Member of 

 the Society. 



1st. A short table, with directions for ascertaining the time ap- 

 proximately by the position of the constellation of the Cross. For a 

 rough estimation, it may be remembered that the Cross is vertical 

 above the pole at midnight 21st March, and vertical below the pole 

 at midnight Sept. 23rd. 



2nd. Observations of the variation and dip of the needle, made on 

 the passage home in 1829, round Cape Horn : and, 



3rd. Currents. 



"The waters of the Pacific being supposed higher than those of 

 the Atlantic, I expected an easterly current on approaching Cape 

 Horn, but I could discover none. Near the northern coast of the 

 Brazils and Guiana we experienced strong currents to the west, in 

 conformity with Humboldt's theory of an indraft into the Caribbean 

 Sea, occasioned by an equatorial current." Mr. R. gives a table of 

 comparison between the ship's place by observation and that obtained 

 by the log, with the drift and force of the current for twenty-four 

 hours. 



4th. " Sargasso Weeds. — In the North Atlantic Ocean, coming 

 from the south, you fall in about the tropic with the Sargasso weeds, 

 collected in narrow lines extending in the direction in which the 

 trade wind blows, that is, E.N.E. and W.S.W., and the eye cannot 

 see the end of them on either side of the vessel. These lines run 

 constantly parallel to each other, and the nearer you come to the 

 middle of the Sargasso Sea the thicker it is strewed with weeds, and 

 the closer the lines approach to one another, being in some places 

 but fifteen feet asunder. Home-bound ships have abetter opportu- 

 nity of observing these lines, as they cross them nearly at right 

 angles, and can trace their continuation more conveniently on both 

 sides, observing one line after another in rapid succession. 



*' These weeds occupy the zone from about 20° to 35° north lati- 

 tude, which may, however, differ according to the longitude in which 

 you cross it. Towards the zone's northern extreme the weeds are 

 less regularly formed in lines, which may arise from their being less 

 methodically acted upon by the trade-winds that seem to occasion 

 their order. They have been termed gulf-weeds by sailors, who 

 believed them to be driven out of the gulf by the Florida stream - } 

 nor is this opinion entirely refuted by the experience that they are 



3 N 2 rarely 



