1839] 



and Set of the Tides at Madras. 



145 



Collecting these several results it appears that the amount of tide ex- 

 perienced at I.Iadras, is 



The above observations and results are the best under the circuni" 

 stances attending them that I have been able to obtain ; in addition to 

 these I have but little to state, and that little being more the result of 

 casual ihan precise observation, of course is entitled to proportionally 

 less credit. To sura up the whole, it appears that, on an average of 40 

 yertrs, the north-east monsoon sets in on the I9th day of October, be- 

 ing very rarely as much as 10 days earlier or later ; and that, although 

 the north-east v\ind continues generally until the middle of February, 

 still the force of its effect seldom extends beyond the lOth of December, 

 It furiher appears that commencing with the N. E. wind, a current of va- 

 riable velocity sets in from the north, in a direction parallel with the 

 shore; and that it generally increases in strength in the course of the 

 day, aiid decreases during the night,* and is moreover influenced by the 

 strength of the wind ; the current appears to reach its maximum veloci- 

 ty about the 1st of November, when in conjunction with the tide it 

 amounts to three miles per hour; and from this time decreases until the 

 10(h of December, when it amounts to a small fraction of a mile per 

 hour only. During this interval, the sea, upon a squally day — such as it 

 would be dangerous if notimpossible for boats to go oiTon,— may be stated 

 to rise two and a ha f feet above, and to sink as much below, its mean 

 level -—an I in the case of a gale of wind it may possibly reach to the 

 double of this amount. 



Varying with the run of the sea is the height of the surf, and the dis- 

 tance from the shore at which the outer surf breaks ; being modified 

 however by the wind and current. In a squally day, sudi as would be 

 d.in;?. runs to cataraarams or boats, tlie outer surf breaks at a distance 

 of 4 0 feet from rlie shore, and in the case of a gale of \vind,t the surf 

 brok^^ on the outsi le of the nearest buoy (which is 828 feet from the 

 shoret) : but on occasions of this nature the swell, breakers, and surf 



* This rem u'k although notinvariably confivmerl by the foregoing observations, is ne- 

 vertheless I believe g(nitnally tru;' : the catamavam men and boat men state that the 

 current is always stroi^^er hi t'le alternoon than in the ra )raing 



t The very hit^h surf expe' ienced on tbf 6th December, although not resulting from 

 a gale of wind at Madras, ev identify huii its origin in one at no great distance. 



t 1 Was uut at the beach on this day ; but from the testimony of the Master Attendant 

 aud his dei)uty there can be but little doubt of this statement being correct. 



Auioant of tide. 



High water. 



I. 



H. M. 



At the new and full moon 2 10 

 At the quarters. 1 9 



