86 



D. Praiii — On the present condition of Barren Island. [May, 



on each occasion. There appears to have been more water in the 

 spring at the time of Mr. Mallet's visit (Feb.) than when our observa- 

 tions were made (April) for he found it possible to take temperatures 

 in seven places while we could only do so in five. 



This spring was formerly much hotter than it is now, but unfor- 

 tunately the early observations are not at all definite : ' as hot almost 

 * as if it had been boiling ' (commander of a vessel, 1832) ; ' tempera- 

 ture too high to be borne with the hand ' (Playfair, 1837) ; ' natural 

 boiling spring' (Mouat, 1857); ' nearly at the boiling point ' (Liebig 

 1858); 'scalding hot' (Parish, 1862). The observations made since 

 1862 being more precise are here appended : — 



Date. 



Temperature of Spring. 



Authority. 



April, 1866 



158° F. and 163° F. 



Andaman Committee, 

 Report in Proc. As. Soc. 

 Beng. 1866, p 213. 



March, 1873 



130° F. (highest observed) 



Ball, Hec. Geol. Surv. 

 India, vi, p. 87. 



February, 1884 



106°— 116° F. 



Mallet, Mem. Geol. Surv. 

 India, xxi, pt. 4, p. 26. 



April, 1886 



110° F. (solitary observation) 



Daley, Bee. Geol. Surv. 

 India, xx, 48. 



April, 1891 



102° -106° F. 



Prain. 



The observations given in this table are not of quite equal value 

 because they have not been taken on a uniform principle. The Anda- 

 man Committee above referred to (Dr. Gamseks, Lt. Laughton and Mr. 

 Homfray) describe the spring accurately as issuing from underneath 

 the lava across the small bay, but though Mr. Ball (I. c.) speaks of 

 them as recording the temperature " at from 158° to 163° " the state- 

 ment in their report is that at low tide in one place the temperature 

 was found to be 163° ¥., and at another 158° F. We cannot there- 

 fore be certain that these figures give either the maximum or the 

 minimum temperature in 1866, though it is highly probable even if one 

 of them represents a limit that they do not exhibit the full range of tem- 

 perature at that time. Mr. Ball's observation, is rather more precise ; 

 the highest temperature is given as 130° F. taken close to high-water 

 mark where the spring bubbles up ; unfortunately he does not give the 

 range of temperature in 1873. In connection with this it should be 

 noted that Mr. A. 0. Hume, speaking of this very observation, says 



