THE DEFENCE OF SYDNEY HARBOR.

Evening Star, Volume VIII, Issue 2487, 4 February 1871, Page 2

THE DEFENCE OF SYDNEY HARBOR.

We take the following from the Sydney Morning Herald :—

The commission appointed to confer upon the best method of defence for Sydney Harbor recommend an outer and inner line of defence. The “outer’’line of defence consists of a baitery at Middle Head of seven 68 pounders, a battery at George’s Head of three 68-pounders and lOin. guns; batteries at the South Head, whsre two 110-pounder »Armstr ng guns are to be planted, two 68pounders, and two Sin. guns; booms from the Sow and Pigs shoal to George’s Head_ aud Lady’s Bay; a double line of torpedoes' placed outside the booms; and casemated batteries, consisting of three 82-pounders, at each end of the boom; and a battery of two 68-pounders at Shark point. The “ inner ” line of defence will comprise one 68-pounder and two 10-in. guns at Bradley’s Head; one 6S-pduuder and foijr 10-iu. guns on Garden Island, six 32-pounders on Goat Igland, three I3in. mortars at Port Phillip, one Sin- and three 32 pounders at Fort Denison, two lOin. and four 32-pounders at Mrs Macquarie’s Chair, five 42-pounders at Fort Macquarie, and five 42-pouuders at Dawes’ Point. The two 110-pounder Armstrongs will sw.eep a radius of at least two miles seaward, and they will also command the North Harbor, .Middle Harbor, and westward in the direction of Bradley’s Head. Another gun of large calibre—portion of the armament ordered from England will be placed at the edge of the precipice higher up and it will have a similar range. The position of five guns near Camp Cove is marked out, and they can be brought tq bear upon a vessel immediately it enters the Heads. The battery at Middle Head will also have a range seaward, and no sooner can a ship enter the Heads, than it will be raked by a’ cross fire from the batteries we have named. In addition to the two cremated batteries, to protect the boom from injury by boat crews, there are twenty-two guns which will concentrate their fire upon any ship which may attempt to force past the boom. The ship would not be far frpm a n Y battery; and our artillerymen, who have the reputation of being good shots, would no doubt be able to smash up any vessel of the stamp we may expect, before she would be in a positiofl to venture upon that hazardous experiment. The boom will consist of' pine logs, 3ft, square, held together by a strong wire rope, fliu. in diameter, and it will 1 be anchored by means of large bio ;ks of stone, to which it will be fastenecj by ringbolts. While it will thus yield to the pressure of a ship, it will at the same time offer sufficient resistance to deaden its way. It is considered to be capable of pulling up the largest ship.’ Tenders are about to be called for torpedoesj each to hold 10001b of powder, and they are to be So p’aced that a vessel must come within 20ft. of one of them. -The - cases are to be made of ij-iu, iron, 'and when filled are

believed capable of blowing up the largest ship. Jn addition to the fixed battene*. the Government have five 40-pounder Armstrong guns available as field artillery ; and the only practicable landing-places at Middle Harbor or Watson’s Bay, will be • commanded by artillery, and defended by entrenched camps, that Middle Harbor being for 200 men. A military road is being made from Bradley s Head for two or three miles in the direction of St. Leonard’s; and from that, roads will branch off to George’s and Middle Heads. These roads will be a chain wide. The road to the head of Botany Bay is finished ; and there are, therefore, ready means for the movement of artillery in that direction. Two guns will be stationed at Botany to protect the waterworks from the attack of boat s crews. The water of Botany Bay is so shallow that a vessel entering that harbor would do so at great risk, and would not be able to get within two miles of the waterworks. Up to the 6th inst. upwards of IUO eligible men had offered themselves for enlistment in the military force which the New S nth Wales Government proposes to establish_ tor the purpose of local defence. The force is to consist of artillery and infantry ; but the strength of each branch of the service, and the period of enlistment, are matters which have not yet been definitely determined The pay will be equal to that received by the Imperial troops, with the Colonial allowance, and perhaps some other advantages added.