• 



1869.] Mr. H. F. Blanford on the Origin of a Cyclone. 473 



from the 23rd to the 27th of October ; also the temperatures and humidi- 

 ties of the atmosphere at land stations at the hours of observation, and 

 the prevalent wind -directions for the same period. The barometric read- 

 ings are throughout the paper reduced for temperature and sea-level, and, 

 with one exception* (noticed below), the instruments have been compared 

 and corrected to the Calcutta standard. 



Noon Barometric pressures. 





23rd. 



24th. 



25th. 



26th. 



27th. 







29'912in. 



? 



30-014 in. 



29-939 in. 



29 926 in. 







•913 



29-967 in. 



29-983 



•940 



•965 







•963 



•999 



30-005 



•943 



•965 







•965 



•972 



•008 



•932 



•953 







•901 



•940 



29-939 



•908 



•928 



Akyab ,. 





•910 



•933 



•939 



•900 



•901 



Madras 





•897 



•926 



•949 



•993 



•930 







lat. 1 











'Prince Arthur,' S.S. - 





S.S. long. \ 



Between Calcutta and Port Blair. 



Port Blair. 





bar. J 















lat. 15° 34'N. 



17° 50' N. 



18° 36' N. 



19° 6'N. 



20° 10' N. 



'Winchester' 





long. 89° 43' E. 



89° 14' E. 89° 8' E. 



88° 46' E. 



? 







bar. 29-894 in. 



29-834 in. 



29-966 in. 



29-931 in. 



29-972 in. 







lat. 8° 12' N. 



9° 53' N. 



12° 17' N. 



14° 3' N. 



1 d° 47' N 



I'i 11 1 1 . 



'St. Marnock' ... 





long. 88° 54' E. 



88° 49' E. 



88° 55' E. 



88°31 , E. 



88° 36' E. 







bar. 29-833 in. 



29-901 in. 



29-903 in. 



29-936 in. 



29-896 in. 







lat. 5° 47' N. 



7° 44' N. 



8° 20' N. 



10° 16' N. 



11° 21' N. 



* J. C. Botelbhoe.'- 





long. 91° 20' E. 



91° 30' E. 



92° E. 



91° 24' E. 



91° 38' E. 







bar.-f 29-770 in. 



29-772 in. 



29-777 in. 



29-740 in. 



29-750 in. 







lat. Galle. 



6° 27' N. 



10° 21' N. 



Madras. 



15°43'N. 



'Mongolia,' S.S. * 



jlong. harbour. 



81° 25' E. 



81° 32' E. 



Roads. 



82° 51' E. 



bar, 29 928 in. 



29-904 in. 



29-946 in. 



29-918 in. 



29-986 in. 





r 





2° 14' S. 



0° 29' S. 



3° 44' N. 



7° 5'N. 









89° 47' E. 



p 



92° 25' E. 



92° 6' E. 







29-804 in. 



29-828 in. 



29-707 in. 



29-562 in. 





- 







4° 56 r S. 



2°59'S. 



0° 8' S. 











89° 27' E. 

 29-886 in. 



89° 24 'E. 

 29-816 in. 



7° 0'S. 

 87° 4' E. 

 29-834 in. 



89° 56' E. 

 29-786 in. 

 4° 31' S. 

 87° 30' E. 

 29-812 in. 





















1 













the march of the barometer that they may safely be accepted as within -02 of the 

 truth. 



* The Madras barometer should be included in this remark, but being an excellent 

 standard instrument, it may fairly be assumed that its difference, if any, is insignificant. 



t The barometer of this ship has not been compared with the standard, but from a 

 comparison of its reading at a later date, at the Sandheads, with that of Saugor Island, it 

 may be inferred that its error is small, not exceeding '05 inch, and probably less. For 

 the purpose of comparison, I have added *04 to the reported readings. 



2 n 2 



