CHEMISTRY. 



Art. LXI. — Note on the Analysis of a Mineral Water from 



the Otira Gorge. 



By Geoege Gray, F.C.S., Lecturer on Chemistry, School of 



Agriculture, Lincoln. 



[Read before the Philosophical Institute of Canter bury, Uh July, 1889.] 



The sample of water referred to in the present note was col- 

 lected by the writer on the 21st January, 1889, in the Otira 

 Gorge, from a spring which is stated to have been first dis- 

 covered shortly after the earthquake of the 1st September, 

 1888. The spring is situated about three-quarters of a mile 

 from the Otira Hotel, up the gorge, just below the road, and 

 flows into the river-bed from the rocks forming the bank. In 

 addition to the one from which the sample was taken, three 

 other smaller springs formerly existed — two warm, and one 

 cold ; these, however, were covered up at the time by the 

 .shingle of the river-bed. The main spring flowed into a pool 

 about ift. in diameter, the sides of which, and the surrounding 

 shingle, were incrusted with a white deposit of sulphur. The 

 smell of sulphuretted hydrogen was perceptible for some dis- 

 tance down the gorge, and it is stated that tlae same was 

 noticed previous to the earthquake. 



The temperature of the water was found to be 87° Fahr., 

 while that of the river flowing by its side was 50° Fahr., and 

 of a stream flowing into the river a little higher up the gorge, 

 46° Fahr. The temperature of the air at the time (7 a.m.) 

 was 61° Fahr. The temperature of the spring is doubtless 

 lowered by the pi'oximity of the river- water, which flows close 

 to it. 



The appearance of the water was of a slightly-dark colour, 

 but clear ; the taste unpleasant, but after the removal of the 

 sulphuretted hydrogen the water became palatable. Ex- 

 posed to the air, a turbidity, due to separated sulphur, was 

 produced ; but after a short time this disappeared, and the 

 water again became clear. No change was produced in the 

 water by boiling other than an evolution of a portion of the 



