1826.] of the Length of the Pendulum at the Equator, 28^ 



chronometer ; the loan of two other chronometers may possibly' 

 be obtained, or two may be purchased. Sextants and artificial 

 horizons may also be taken from the Observatory, with a tele- 

 scope and a portable transit instrument. A barometer and 

 some smaller articles must be purchased, and levelling ami 

 measuring rods be made up. Also the loan of such surveying 

 instruments ■ as may be required, can be obtained from one or 

 more of the pubhc offices, where such are in store. By this 

 arrangement, the expense will be as limited as possible ; and I 

 have no doubt, that future and not inconsiderable expense will 

 be saved, by the geographical information which will be coir 

 lected during the operations, and which, being extremely 

 required by Sir T. S. Raffles, the assistants may be instructed 

 to omit no opportunity of obtaining : points must necessarily be 

 established, and that in the most accurate manner, from which 

 those employed in the ordinary operations of surveying, may, 

 at all times, take a departure. Sir T. S. Raffles, in a communi- 

 cation to me, observes, ' I lament to say that our geographical 

 knowledge, even of the coast, is most defective ; with the 

 exception of Acheen Head, and Bencoolen, and, perhaps. Flat 

 Point to the south, neither the latitude or longitude of any place 

 along the whole line of coast, is laid down correctly. I am 

 endeavouring to supply the deficiency, but I am in great want 

 of scientific assistance, and get on but slowly. The Poggy 

 Islands and Pulo Nias appear to be laid down not less thaa 

 40 miles to the westward of their true situation ; and no two 

 charts agree in the longitude of the main island to the northward 

 of Bencoolen. I mention this in order that your observations 

 may commence at Madras, and be brought on direct to Benr 

 coolen.' The sooner. Sir S. Raffles observes, the party are at 

 Bencoolen ^ after January the better ;' and opportunities, it is 

 probable, may occur, for sending them in a vessel bound to that 

 place. 



• " Should the Honourable the Governor in Council be pleased 

 toi direct these operations to be performed, 1 can prepare the 

 assistants for the execution of the duty, and frame detailed 

 instructions for their guidance. A list of the articles required 

 for the expedition can also be submitted for approval." 



This letter was dated the 6th of November, 1821, and a most 

 gratifying reply was received to it on the 16th of the same month, 

 of which the subjoined are extracts. 



^'^^ I am directed to acknowledge the receipt of your letter of 

 the 8th inst. and to state, that the Honourable the Governor in 

 Council, fully sensible of the importance which is to be attached 

 to the observations you are desirous should be made at the 

 Equator, will be happy to afford every possible assistance in 

 the prosecution of researches which are calculated to prove so 

 '^etuinently valuable to general soienceifcqj'^ nwwt.iMi/i- ? -^ 

 'KVJ .i-* , ddU odJ moil 9JiIi^ ^ tol 



