Haast. — On the Hot Springs of Hanmer Plains. 415 



station in Christchurch. During my first visit to the Hanmer Plains I was 

 informed by one of the residents that the temperature of these springs 

 altered considerably according to the seasons and the state of the weather, 

 a fact confirmed by a communication of Dr. Hector made to the Superin- 

 tendent of Nelson in October, 1870, and printed in the same volume of the 

 "Transactions,"* in which he gives the main results of his examina- 

 tions of the same springs on 8th May, 1867. In comparing these observa- 

 tions it appears that the temperatures of the different springs recorded by Dr. 

 Hector are much lower than those obtained by me, and although I am not 

 able to recognize with certainty the different springs as indicated by him, 

 there is evidently a great difference, his highest reading reaching only 90-5°. 

 However, as his visit took place in the autumn, the temperature of the air 

 being only 52°, it is possible that at least to some small extent this may 

 account for his low readings. In order to obtain reliable results, my obser- 

 vations were always taken at the same spot, for maximum temperature of 

 each spring the thermometer being lowered to the bottom, whence the 

 bubbles of sulphurous steam rose up most conspicuously, and where, after 

 several tests, I had found the water possessing the highest temperature. 

 The surface temperature on the other hand was always taken in a similar 

 manner, the instrument being immersed for five minutes at the same spot. 

 In such a manner the readings were uniform throughout. 



In case of a great difference of the readings with those previously noted, 

 I always took a second observation in order to obviate any possible error. 

 The appended list of thermometric readings of the thermal springs shows 

 convincingly that even in not more than 24 hours the difference reached in 

 some instances is as much as 13 degrees Fahr. The temperature of the 

 springs was always highest during easterly weather. On the 2nd of January 

 the centre of the principal pool used for bathing purposes reached 120 

 degrees ; on the 5th of January, also, whilst a stronger easterly wind was 

 blowing than on the 2nd of January, 116 degrees were recorded. The 

 lowest reading, 93 degrees, was obtained on January 7th, when a strong 

 north-wester was blowing. 



These facts are in accordance with the experience of the inhabitants of 

 the neighbourhood, who had previously informed me of this curious phe- 

 nomenon. 



It would be premature to attempt its explanation for the present, but 

 the recorded facts point towards the necessity (if these springs are to be 

 used for medicinal purposes for which, from the cures effected, they are 

 qualified in a high degree), that at least the principal springs have to be 



* I.e., p. 297. 



