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 18 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 tlie 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 
* Le., p. 297. 
