Double Rainbow Over Arnos Grove!

A rare double rainbow provided the backdrop to works in North London, where Quattro machines were supporting a London Underground siding upgrade.

The works, carried out for TfL's ballasted track team, involved excavating to formation level ahead of new track installation. The upgraded sidings will accommodate the forthcoming new Piccadilly line trains, which are longer than the current fleet.

Our thanks to John Pugh, Plant Approvals Manager for TfL's ballasted track team, for sending in this photo, which captures Quattro RRVs at work on site as the project progresses.

If you want the science... a secondary rainbow occurs when sunlight is reflected twice within raindrops, making it fainter than the primary rainbow and reversing the order of the colours.

As Jon Sherred, Area Manager, commented:

There had to be a pot of gold somewhere!

Quattro Managing Director, John Murphy added:

If anyone finds the pot of gold, let me know. We've got three machines here ready to dig it out!