Ask Phoebe: Britomart's silver poles will power electric trains inside the station

Photo / Sarah Ivey

Q: What are the new silver poles hanging from the roof in Britomart? Are they merely for decoration and someone's amusement, or do they serve a purpose?

- Mary Christiansen, Auckland CBD.

A: They certainly are more use than ornament. These are the newly installed overhead conductor rails inside Britomart.

The conductor rail system will be used to power electric trains inside the station and has been used because of challenges faced in fitting electric wires within a confined space and as a way to minimise visual impact within this historic building.

"It has always been important for us to find a solution that is in keeping with the architectural integrity of the building and I think we have achieved that," says Nick French, KiwiRail's director of the Auckland electrification project.

And, somewhat out of area, but of general interest, I think:

Q: Why is Fiordland in the South Island so called, when most of the features are called sounds, eg, Doubtful, Milford, etc? Was it someone's lack of knowledge of geographical terms?

- Pauline Fish, Birkenhead.

A: It seems so. The area was gazetted as Fiord County in 1876 and was established as a national park in 1952.

Strictly speaking, the sounds in Fiordland are fiords. A fiord is a deep, glaciated valley, typically long, narrow and steep-sided, that has been flooded by the sea as a result of rising sea levels and tilting or depression of the land, or a combination of both. The Marlborough Sounds were formed like this as well.

In Fiordland the fiords are invariably called sounds except for the two big inlets (Preservation and Chalky) in the south of the area. To confuse things even further, the largest arms of nearby Lake Te Anau are called fiords, even though they are some distance from the sea.

(Source: Wild Fiordland by Neville Peat and Brian Patrick, a quite splendid and informative book.)

Q: Having recently visited Fiordland [so nice to have a theme: Ed] and having been attacked and pestered by sandflies, I began to wonder - what do sandflies feed on when I'm not there?

- Rodger Ferguson, North Shore.

Q: They (female sandflies only) feed on other vertebrate fauna such as birds, lizards, bats and seals. This is why they are so abundant at the edge of forests or on a beach.

Male sandflies (or blackflies, mainly Austrosimulium ungulatum) are seldom seen as they feed on sap. The females need blood to get protein for additional batches of eggs. The irritation the bites cause comes from the anticoagulant the insect uses to stop the blood it draws clotting in its proboscis. (Source: as above)

• And a belated clarification: Safety improvements underway at the SH1/Wayby Valley Rd intersection are not linked to the Puhoi to Wellsford "road of national significance", as reported recently. The intersection is a crash black spot and it needs upgrading as the eastern beaches in the area grow in popularity. The project at Hudson Rd is the latest in a series to improve access and safety along SH1 through Warkworth.