UA Kaa AA etm 
Pond.—Notes on a Salt Spring near Hokianga. 518 
The spring in question is situated in dense bush, on the dividing range 
between the Wangape and Waihou rivers, the latter of which runs into 
Hokianga Harbour. The distance from the sea in a direct line is about 
nine or ten miles, and is at a considerable elevation above sea level; hence 
the presence in large quantity of chloride of sodium is highly interesting, 
showing, as it does, that there must be in the locality a deposit of salt, 
probably some distance below the surface, which I should judge from the 
fact of its not being more highly impregnated. As will be seen by the 
analysis, this water contains about the same percentage of chloride of 
sodium as ordinary sea water, but differs therefrom in the absence of sul- 
phates. The following gives the chief constituents, so far as the small 
quantity of the sample at my disposal would permit :— 
The solid matter equals 2937-558 grains per gallon, composed of— 
Organic matter su P 51:115 
Soluble silica uis iv vs ba 49:562 
Carbonate of Magnesia ae ES be 18'710 
Chloride of Potassium we eh ae 1:9 
3 Sodium m S .. 27914 
Lime and Iron a ya P .. traces 
Mss Acid 
Los 18- 871 
The sample was MEN Ce. k a very eR amount of fine sedimentary 
deposit, which proved to be silicate of alumina, with a trace of iron and 
lime. After standing some days the water was opalescent, acid reaction 
and strong saline taste. From the appearance of the deposit, and a few 
fragments of gravel brought separately, I should judge the locality from 
whence the water was taken to be of a clay-slate formation ; but during the 
coming summer I hope to make an examination of the place in which this 
spring is situated, and a further one of the water. Spectroscopically I could 
not detect lithia. As I have already mentioned, this spring ranks higher 
than any other in this Colony, so far as records show, in regard to the 
amount of alkaline chlorides present. 
While speaking with respect to springs not included in Mr. Skey's 
report, I will add some information respecting two other mineral waters 
from our district which have been analyzed. The first is located near 
Whangarei, and is highly charged with carbonic acid gas. The springs 
are surrounded with a vitreous-looking silica, and in places with large 
quantities of a very light porous rock, presumed by the residents at first 
to be meerschaum, but this I find on examination to be incorrect, the 
chemical tests showing it to be a silicate of alumina, and the microscope 
resolving it into an infusorial earth, well worthy the consideration of our 
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