2'2G Obsercatiotis on the Dhection and Intcntt'lif of the [ArniL 



workman (m the prison attaclicil (d Trivundriwn Obsorvuloiv, for flu- 

 purpose of repairinij instrnnionts, I procMucil tlic rc-turning of the 

 }Hvotsof tlif hitherto useless needles (No. 2 and 4), and the i-onslnidion 

 ol two new intensity needles. 



Thus eijuipped I left Trivandnnn on the 20th Sejiteniber, and eniph)y- 

 ing all lour of the dipping needles and five iniensity needles— which 

 practice had now enal)led n.e to aeeoni]ilish unassisted — I a«;;rm made 

 observations at those places which had hitherto given contradictory re- 

 sults; and eventually arrived at Madras on the l5th October. 



It had been agreed ujion by Mr. Caldecott and myself, that, beforo 

 completing the observations to the northward of Madras, the instru- 

 ments should be sent to him, to perform a portion of the work to the 

 northward of Trivandrum ; this was done, and tlu> observations, as far as 

 Tellicherry, were made by Mr. Caldecott, in the month of November 

 follow ing. It had been Mr. Caldecott's intenti«m to have completed the 

 series on the western coast at a no very distant dale : but the uusatisfac- 

 toiy results now arrived ;it, induced him to await the arrival of a new 

 dip apparatus and needles from laii^land (which he had ordered of Mr. 

 Thomas Jones for this purjiose), and lo return the needles lo mo for the 

 prosecution of the observations on this coast. I was anxious for the 

 completion of the work, but had already been too long absent from the 

 Observator}', whereby computations had accumulated, and observations 

 had been neglected to some extent ; thus circumstanced, I availed my- 

 self of the services of a very intelligent and careful native (Tannyachel- 

 lum) who, after making observations on the dip and intensity every day 

 during three months, had acquired as correct a habit of observing as 

 could be expected or desired. Tannyachellum accordingly was des- 

 patched from Madras on the 27th April 1838, with directions to make 

 observations 'of the dip and intensity at distances of about 25 miles apart* 

 from hence, along the coast as far as Ongole; and to re-observe at the 

 same places on his return. This was accomplished by the end of June ; 

 and with the exception that the dip observations were made in the usual 

 way, not our method of " vibrations,'' I venture to assert that the 

 results he has obtained, are not less accurate than I might have arrived 

 at myself. 



The new dip apparatus by Jones, much to our disappointment, did 

 not arrive at Madras till September 1838, just before Mr. Caldecott's 

 departure for England : on examination it appeared in every respect to 

 be a very superior instrument ; but the results arrived at here, both by Mr. 

 Caldecott and myself (Mr. Caldecott being at Madras by this time) were 



