102 



Native Mariners of 



[No. 37, 



ed with a string suspended from its centre, eighteen inches long. 

 A number of knots are made in this string indicative of certain 

 previously observed latitudes ; in other words, coinciding with the 

 positions of certain well known places on the Coast. The posi- 

 tion of these knots is obtained in the following manner. The ob- 

 server elevates the board in his left hand, its longest side being 

 upwards, and draws it backwards and forwards in front of his eye 

 until its upright length exactly corresponds with, or covers the 

 space included between the polar star and the horizon. With 

 his right hand he nest catches hold of the string and brings it to 

 his nose, he makes a knot at the point where it touches that fea- 

 ture ; and if he at the time be abreast of Point Palmiras, an unde- 

 viating index is afforded, which will in future show him when he is 

 oft' that point, the North star's elevation being always fixed, and 

 therefore all the parts of the triangle formed by his line of sight, 

 the string, and the distance between the polar star and the hori- 

 zon or the length of the board, equally as constant. To make the 

 thing as clear as possible, suppose the observer find when out at 

 sea, that the knot which measured the former coincidence of his 

 position with Point Palmiras, again impinges on his nose, he is sa- 

 tisfied, on this occasion, he is in the same latitudinal line, as he was 

 on that, or that he is off Point Palmiras. 



He makes similar observations at, and a knot is fixed opposite 

 each conspicuous place, on the length of the string,- as far as Don- 

 dra Head in Ceylon generally. Thus by a simple observation, at 

 any future time the Mariner is enabled to ascertain his position 

 with sufficient accuracy for his purposes, anywhere on the coast 

 between Calcutta and the South point of Ceylon. 



The two drawings refer to this subject 



