THE ISLANDS OP THE BAT OF BENGAL. 31 



extends right through Sumatra, Java, and the rest of that chain 

 of islands, to New Guinea. 



The relative positions and dimensions of the several islands 

 may be gathered from the sketch map already referred to, 

 but it may be useful to note, once for all, the lengths of some 

 of the more important breaks, and links, in the chain. 



These islands have never yet been very accurately surveyed ; 

 in fact the chief materials for the chart of the Nicobars are 

 derived from the very partial surveys executed by the Novara 

 Expedition, but the distances below noted are approximately 

 correct. From Cape Negrais to Preparis, 85 miles ; Preparis 

 to Great Cocos, 50 miles ; Great Cocos to the northernmost 

 point of the Great Andaman, 45 miles; total length of the 

 Great Andamans, 135 miles: Macpherson's Straits divide the 

 latter from Rutland Island, which is about 10 miles in length, 

 and distant about 35 miles southwards lies the Little Andaman 

 itself some 27 miles in length. Then comes a blank of 80 miles 

 before we reach Car Nicobar, the northernmost of this group. 

 Tillangchong and. Teressa, which are about 40 miles apart, 

 are each distant some 60 miles from Car Nicobar ; and from 

 this latter, Camorta Harbour, which lies in the middle of the 

 four central islands, Nancowry, Camorta, Katchall, and Trinkut, 

 is distant about 90 miles. From Katchall to the Little Nicobar 

 is about 35 miles ; the Little and Great Nicobar together are 

 some 50 miles in length, and between 60 and 70 miles south- 

 east of the latter we come to Pulo Way, one of the small islands 

 lying off Acheen Head. 



In regard to the climate and meteorology of these islands, I 

 prefer, instead of recording any crude notions of my own, to 

 quote a brief note kindly prepared for me by Mr. H. F. Blanford, 

 our first Indian authority on such subjects. 



" The temperature of the Andamans, as might be expected 

 in the case of tropical islands, is very uniform ; the coolest 

 month (January) has a mean temperature of 78-9°; the warm- 

 est month (April) one of 83'9°, a difference of only 4°. 

 The highest and lowest temperatures recorded during the six 

 years 1868-73 were 96° and 67°, respectively, and the absolute 

 range during the period has, therefore, not exceeded 29°. In 

 most months of the year the average daily range is from 8° to 

 10°. From February to April it is somewhat higher, and in 

 March, in some years, it is as much as 14°. 



u The mean humidity of the air is about the same as that of 

 stations on the Arakan coast of the Bay, and in the day time aver- 

 ages between 62 and 88 per cent, of saturation. March and 



