138 



Report upon the Run of the Sea, 



[Jan- 



On comparing the foregoing register with similar ones during the last 

 forty 3^ears, it appears that the monsoon of 1838 has not been particu- 

 larly distinguished — either for its severity or mildness; and from the 

 evidence of the shipping in the roads, it would appear that a monsoon 

 of full ordinary strength has been experienced. With regard to the 

 particulars of the observations from which this report has been drawn 

 lip, I may at once proceed to state, that 



The Site cho sen for making the observations, was a long range of 

 verandah, situated in front of the Sea Custom House and Master At- 

 tendant's Office ; at about 200 feet from the edge of the sea and 29 feet 

 above its mean level— immediately opposite to the spot on which stones 

 had been thrown down for the proposed breakwater. On this verandah 

 two stations were selected, 205 feet apart (which I have distinguished 

 as the north and south end of the verandah), from which I was enabled 

 to determine the situation of buoys, &c. 



The InstruiMents employed on shore, were, a five feet achromatic by 

 Dollond (fitted with circles of 4 in. diameter, reading off to minutes, for 

 the measurement of altitude and azimuth, and supplied with a position 

 and double wire micrometer), and a 9 inch theodolite by Dollond — both 

 circles reading off to minutes. 



The Apparatus employed at sea, consisted of a small iron buoy (No. 

 1), anchored in 18 feet water, immediately opposite to and 828 feet dis- 

 tant from the S. station ; and a similar one (No. 2), situated at 1131 feet 

 distance from the same, and exactly in a line with No. I : both of these 

 buoys were held to their anchors, with 6 inch coir cable of 18 fathoms in 

 length. In addition to this, a canoe of 16 feet in length, decked over and 

 well caulked, was anchored opposite to, and 1200 feet distant from the 

 north station ; the canoe was furnished with a slender rod of 8 feet in 

 length, nailed to the deck at right angles to its length, for the purpose of 

 indicating the direction of the current; and an apparatus (fig. No. 1) for 

 measuring its velocity : — Vv'here A represents an iron flanche, which is 

 screwed on to the stern of the canoe and supports a double jimbol E, 

 on which the connected iron rods D B and B C and wooden bob C, 

 are free to move in every direction. In the case of no current — E 



