908 



a uue si vaste eutreprise a diriger que la iiotre, et lorsqu'il s'agit 

 de tirer au clair tons les resultats quelle promet. Combien ne se 

 perd-ii pas d'argent, de temps et de peines, par des efforts isoles, qui 

 coordonnes convenablement et diriges vers un but commun porte- 

 raient les plus beaux fruits? Combien de donnees precieuses pour la 

 science ne voient jamais le jour, faute de moyens de les publier? 



Je n'hesite pas de dire, que la fondation d'un observatoire phy- 

 sique central en Angleterre me parait etre d'une grande necessite 

 dans I'etat actuel des sciences d'observation, et que I'exemple donne 

 par le gouvernement anglais et par le notre serait bientot suivi par 

 les autres etats, 



Veuiller agreer les assurances de ma haute consideration et de ma 

 vive amitie. (Signee) A. T. Kupffer, 



Directeur de V Observatoire physique central. 



S. A Letter from Captain C. M. Elliot, Madras Engineers, to 

 Lieut.-Col. Sabine, For. Sec. R.S., transmitted through the Court 

 of Directors of the East India Company. Communicated by Lieut.- 

 Col. Sabine. 



Having undertaken the magnetic survey of the Indian Archipelago 

 at the recommendation of the Royal Society, I think a slight sketch, 

 detailed as briefly as possible, of my operations may not be unin- 

 teresting to Sir John Herschel and the Committee of Physics of 

 which he is Chairman, prior to the publication of the Survey. I 

 trust likewise I have acted strictly in accordance with the wishes of 

 those who so kindly recommended me for the Survey, and I hope 

 that my earnest efforts to do my duty will gain for me that appro- 

 bation which I have under no ordinary difficulties incessantly striven 

 to obtain. 



I will in the first place mention the different stations I visited, and 

 then describe in a few words, the way in which the observations were 

 taken. 



I have made a most complete survey of Java. At Batavia I 

 established an observatory where observations, magnetic and meteoro- 

 logical, were taken hourly from 3 a.m. to 9 p.m. for nine months. 

 In addition, about fifty stations, where observations of dip, of total 

 intensity, of latitude, longitude, and declination were taken ; these 

 were always made by myself, and I am certain they can be depended 

 upon. 



In Borneo an observatory was established at Sarawak, where ob- 

 servations were taken quarter-hourly for three months, besides visiting 

 the Dutch settlements of Sambas, Pantianak and Succadana on the 

 western coast. 



In Sumatra four months of observation at Padang, besides a mag- 

 netic survey comprising about thirty stations. I crossed the equator 

 here as v/ell as at Pantianak in Borneo. 



At Singapore I compared the portable instruments with the fixed 

 instruments of the observatory, besides determining the horizontal 

 intensity and dip, which had not been accurately determined pre- 

 viously from insufficiency of means. 



