Australia - South Australia/Northern Territory.
The Overland Telegraph Line - construction strategy for the southern section.

The first length of 500 miles from Port Augusta extended to about Peake at the latitude of 27° degrees. It was let to Mr. Bagot.

Lower section
All three maps scanned from a plan produced in the 1870s and "compiled from official documents supplied by the Superintendent of Telegraphs".		 Port Augusta was chosen as the starting point for all Government parties bound for the Far North. The Port Darwin Line branched from the main wire between Port Augusta and Clare/Adelaide at a point about four and a half miles from the Port at Stirling North - which is as unlike its namesake of old Scotland as any two places can be.

The Australian town of Stirling was situated on extensive plains consisting of a peculiar calcareous and sandy soil, the surface of which was so easily disturbed by every breeze as to send forth clouds of very fine dust. By reason of the limey nature of the grit, it was most irritating to the eyes. People resident in the place did not complain much of ophthalmia, however — because, like the eels we read of, they have got used to it. To those people who had lived in other climates, the dusty visitations to be experienced at Stirling, South Australia, were things to be remembered by eyes, teeth, ears and cuticle for many days - bath or no bath. Todd said at one point, "he was prepared to aver upon oath that he unwillingly swallowed as much sand during his first two days stay in the place as would have made a moderate sized hearthstone".

Nothing was done initially to erect stations on the first 500 miles of the line. The priority was to provide facilities for repeating stations which were not open to the public — at Beltana, at Strangways Springs and at the Peake.

The Adelaide Observer of 15 July 1870 noted that "the telegraph line had been completed from Port Augusta to Beltana, a distance of 150 miles, and on Wednesday messages were exchanged between Adelaide and the latter place. Mr. Johnston is the field operator accompanying the wiring party. We understand that the poles upon Mr. Bagot's portion of the telegraph line have been erected as far as Mount Margaret, and that the wiring beyond Beltana is being rapidly proceeded with. In a few weeks more communication will be established with the Peake".

On 1 October, 1870 four members of the southern party - Messrs. Servant, Brown sen., Brown jnr., and Everitt (cook) - joined Mr. Abbot, the inspector of the first section of the line (250 miles), and on that day the first pole of the Overland Telegraph was planted. Mr. Towler, manager for the contractors, superintended the operation. The exploit of name-inscribing was of course performed on the post by several people who could not allow so time-honoured a custom to die out.

Two days later the party was again rearranged and Messrs. Boucaut, C. Kraegen, Burton, Brown, jun., and Barton (as cook), left with two provision-laden spring-carts en route for Mount Margaret.

Wallaroo Times of 22 April 1871 noted that "a number of iron telegraph poles have recently been shipped to Port Augusta for the telegraph line across the Continent. They are to be used in that part of the country most liable to bush fires. Others will be sent to Port Darwin. Mr Todd hopes to have communication 800 miles north of Port Augusta by September 1".

On 13 September 1871, the Hobart Mercury updated its readers with:

"About the 10th instant, the operators were to leave Adelaide for the four interior telegraph stations north of Beltana. The batteries left Port Augusta at the end of July and will be at the stations a little before the operators. The four instruments are precisely alike - intended respectively for the stations at the Peake, Lady Charlotte Waters, Mount Freeling on the Reynolds Range and somewhere near the Bonney. For the Owen Springs, an automatic repeating instrument is provided. It is a beautiful piece of mechanism and will be extremely useful preventing the necessity of repeating the message by hand and thus avoiding the possibility of mistake - being in fact equivalent to sending a message along the whole line without a break. The distance is too great to allow of that being done without the assistance of an intermediate battery".

The following is an extract from Todd's 1 January 1873 Report published in the Adelaide Advertiser on 11 January 1873 (p. 11).

On Bagot's contract, extending 509 miles from Port Augusta, or to latitude 26° 52' south, the poles are pine and gum, the latter being mostly considerably over the specified size. There are also about 1,500 iron poles, planted generally alternately with wooden poles, distributed over the line north of Chambers' Creek.

Considerable delay occurred in completing this section, which was commenced in October, 1870, owing to the absence of suitable timber over 300 miles of the line; but by allowing the contractor to put in at first only 10 poles to the mile on the northern end of the contract, the wire was suspended by the beginning of January, 1872, and communication established with the MacDonnell Ranges on the 3rd of January. The full complement of 20 poles to the mile were filled in subsequently, and the contract was satisfactorily completed about the end of March. From personal inspection, I am able to report it a most substantial line which will stand for a number of years with very little attention. This section was constructed under the supervision of Messrs. Babbage and Abbott, the former having had charge of the northern half until he left for England.

On this section, and throughout the whole of the line, a lightning conductor has been placed on every alternate pole. It consists simply of a piece of ordinary line wire, stapled very securely onto the side of the pole, terminating in a coil beneath the butt so that it cannot be withdrawn.

These conductors have proved an effective protection from lightning for although the line for many hundreds of miles passes over treeless plains and is exposed to thunderstorms of great severity and extent, we have scarcely had a pole destroyed by lightning. The only interruptions caused by lightning have occurred where iron poles have been used. Since the line was opened on 22 August we have had three interruptions, all of which have arisen from this cause and have happened on the same section and in the same locality, viz., on the iron poles north of the Hamilton, on the section between the Peake and Charlotte Waters. The lightning in each instance smashed several insulators, leaving the wire in contact with the iron pole thus making "earth" and stopping the communication.

To obviate this in future, I have had a short length of stout wire led from the line wire down the face of the insulator and brought within three-eighths of an inch of the top of the iron pole. This has been done to every iron pole, and will I think protect the insulator. I am having the same done on the wooden poles furnished with lightning rods between the Katherine and Port Darwin where iron insulator pins have been inserted during the last dry season".