THomson.—Glacial Action in Otago. 311 
shells; also the vertebra of fishes of the whale species. Limestone formations 
of somewhat analogous structure are found in the Waitaki Valley, notable for 
their profuse possession of marine fossil remains (a list of which has been 
published by Mr. Traill) and rising with a recorded elevation of 1,059 feet 
above the sea ; but, as the survey has not extended over the whole district, this 
is by no means the limit of elevation to which the formation attains. Then, 
again, in the Waihemo or Shag Valley, a limestone patch of the same age, and 
with similar fossils, occurs, rising to an elevation of 1,428 feet. At Waikouaiti 
another occurs, rising 531 feet. Many others are necessarily unnoticed, but 
mention may be made of those in the southern districts, such as Forest Hill, 
south énd of Turingatura Downs, Point Pleasant, and Oreti plains; also, 
Orawia and Waiau, the limits of whose altitudes I am unable to obtain, but 
which vary from 200 to 1,000 feet above the sea. 
Thus, over a confessedly limited area of New Zealand, ample proof is given 
of the surface of the land having been under the sea level, by these limestone 
formations carrying sea animal remains ; and if we admit the depression to 
have been 1,428 feet, by actual observation, so may we admit a much greater 
if need be. Thus, while we see that the ocean had covered our dry land, so, in 
passing, I may bring to your notice that the converse had taken place. 
In Europe proofs of this are abundant in the fossil trees and plants found 
in the coal mines at a depth reaching down to 2,500 feet below the ocean 
surface. Here, in the infancy of mining, we have but limited examples, but 
as sure in their indications as the others. These we have in the Shag Point 
and Molyneux coal mines, now being worked at the sea shore, and whose dip 
is under it; and at Green Island, where mining is now carried on below the 
sea level. Hence it comes home to the mind that the earth has had no rest, 
but rises and falls in the cycles of geology. But that it has been in practical 
quiescence for 100,000 years we also have close proof and ready assurance, 
as exhibited in the alluvial plain at the head of this harbour (Otago), whose 
formation must have required that, to our standard, enormous period, and 
whose surface shows no indication of rise or fall exceeding at most one or 
two feet. 
Having gained one step in my essay, viz, that in the tertiary period our 
land had been much lower than it now is—for I may meet an objection which 
might be started, that these limestone formations might have been mere local 
upheavals, by stating this to be impossible, they lying on the older formations 
as their basis, and which they do not do at one part only, but in a manner 
enclosing half the circumference of the Province, and inserting themselves 
between the plutonic and metamorphic rocks of Stewart Island and the great 
western range of mountains. 
The next step in my theme is to show that this region was within the 
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