1840.] 



and Mountains of N. W. India, 



349 



second tide, therefore, to render further inquiry necessary, and it would 

 be desirable to employ a barometer for the purpose, which should not 

 require to have any correction applied for the temperature of the mer- 

 cury ; this might be easily eifected, by enclosing the barometer tube in 

 an outer tube of the same length, also filled with mercury, upon the 

 surface of which the scale might float." 



Nocturnal Oscillatioin of the Barometer from 10 p. m. to 5 a. m. 

 reduced to 32° Fahr. 



Month. 



Madras, three 

 daj's in each 

 month. 



1 



Berhampore, 

 from Dr.Russel's 

 tables. 



Saharunpore, Dr. 

 Royle's observa- 

 tions. 



1 



Vera Cruz, in 

 Mexico, by Fray 

 Juan, 





—•004 



+ •034 



—•043 



+ •018 



February 



—•029 



-f -026 



—•009 



+•009 



March 



—•026 



+ •069 



— 008 



— •002 





— •027 



+ •008 



—•007 



+ •008 





—•014 



-^•020 



—•020 



+ •005 





—•026 



+ 012 



+ •039 



+ •003 





—•009 



•000 



—•005 



—■002 





—•028 



+ •014 



—•016 



—•007 



September... 



—•024 



+ •011 



+ •011 



—•012 





— •033 



+ •009 



—•004 



—•021 



November. .. 



—•010 



+ •009 



+ •024 



+ •001 



December.. . 



—•019 



+ •027 



+ •015 



—•023 



Means... 



—•021 



+ •020 



—•001 



—•002 



Saharunpore, as we have seen, is situated nearly at the head of the 

 great Gangetic valley, in N. lat. 29° 57', long. 77° 32' E., one thousand 

 miles north-west of Calcutta, in the Doab, or space included between 

 the Ganges and Jumna rivers, about twenty miles from the former, and 

 nine from the latter, and about thirty miles from the Sewalik or Sub- 

 Himalayan range of Mountains. It is celebrated as the station whence 

 the Trigonometrical Survey of the Himalayas was commenced by Capts. 

 Hodgson and Herbert (Illustrations, Introduction, p. xii.). It was 

 then calculated by Captain, now Colonel Hodgson, to be elevated 1,013 

 feet above Calcutta. Mr. James Prinsep, from my observations, 

 compared with his own, in Calcutta, calculated that my house, situat- 

 ed in the vicinity of the Botanic Garden, was as near as possible one 

 thousand feet above the sea (Journ. As. Soc, vol. i. p, 29). The 

 characteristics of the climate are mentioned at p. 7, of the Illustra- 

 tions in connection with the vegetation, which is described as being 

 tropical at one season, and partially European at another, and as having, 



