Anniversary Address. xxxiii. 
Lyttelton and of the harbour itself. Ripa Island, however— where 
the quarantine establishment is at present placed—is a very favour- 
able site for a work to fulfil these objects, and here I propose that 
there should be constructed a battery by which you will observe the 
whole harbour will be well commanded. This work will be rendered 
perfectly secure against capture by assault, and will also be protected 
against being silenced by a body of men which an enemy might have 
succeeded in landing in the adjacent inlet, called Port Levy, and gain- 
ing possession for a time of the heights overlooking the harbour on 
the southern side. This last operation is one Which, considering the 
precipitous character of the country, I do not conceive to be likely, 
but it is a contingency which, in the design of the work, should 
be provided against. 
The guns on Ripa Island, thus completely secure against being 
silenced or against capture, will absolutely deny the use of the 
harbour to an enemy, and will prevent his taking up a position 
therein with a view of effecting any hostile object. 
It would be desirable, however, to place Some pieces of artillery 
on the North Shore, so as to bring a cross-fire to bear on an attack- 
ing vessel, and to command small bays on the southern side which 
are not seen into from Ripa Island. Torpedo-vessels will co-operate 
with the shore batteries, and will also prevent an enemy lying un- 
molested in Port Levy, Pigeon Bay, or Akaroa Harbour. 
A field-force of artillery and infantry, acting from Lyttelton 
upon the road from Lyttelton to Sumner, would both aid in the 
» defence of the harbour, and effectually prevent any attempt to land 
at Sumner and advance therefrom to Christchurch. 
. DUNEDIN AND PORT CHALMERS. 
Dunedin, situated at the head of the estuary which forms the 
harbour of Otago (see Plate IV.), at about twelve miles distance from 
its entrance, is only divided from the sea by a low neck of land about 
a mile wide, which on the sea-side is called the Ocean Beach. Mid- 
way between the city and the entrance is Port. Chalmers. Durin 
the last few years the water between Port Chalmers and the city has 
been considerably deepened, but Port Chalmers remains the anchor- 
age for the largest ships. 
It has been determined to construct a training-wall at the entrance 
to the port, opposite Taiaroa Head, and ultimately another but shorter 
One, in continuation of that head, with a view of deepening the 
channel. These harbour works will not, however, affect the plan of 
defence. 
As observed by Major-General Scratchley, an enemy may either 
