Positive ground (they meant "earth") depends on proper circuit functioning, which is the transmission of negative ions by retention of the visible spectral manifestation known as smoke.

Smoke is the thing that makes electrical circuits work. We know this to be true because every time one lets the smoke out of an electrical circuit, it stops working. This can be verified repeatedly through empirical testing.

For example, if one places a copper bar across the terminals of a battery, prodigious quantities of smoke are liberated and the battery shortly ceases to function. In addition, if one observes smoke escaping from an electrical component such as a Lucas voltage regulator, it will also be observed that the component no longer functions. The logic is elementary and inescapable!

The function of the wiring harness is to conduct the smoke from one device to another.

When the wiring springs a leak and lets all the smoke out of the system, nothing works afterward.

Starter motors were considered unsuitable for British motorcycles for some time largely because they consumed large quantities of smoke, requiring very unsightly large wires.

It has been reported that Lucas electrical components are possibly more prone to electrical leakage than their Bosch, Japanese or American counterparts. Experts point out that this is because Lucas is British, and all things British leak. British engines leak oil, British shock absorbers, hydraulic forks and disk brake systems leak fluid, British tires leak air and British Intelligence leaks national defense secrets.

Therefore, it follows that British electrical systems must leak smoke. Once again, the logic is clear and inescapable.

In conclusion, the basic concept of transmission of electrical energy in the form of smoke provides a logical explanation of the mysteries of electrical components especially British units manufactured by Joseph Lucas, Ltd.

And remember: A gentleman does not motor about after dark.

Joseph Lucas - The Prince of Darkness

A few Lucas quips:

The Lucas motto: Get home before dark.

Lucas is the patent holder for the short circuit.
Lucas - Inventor of the first intermittent wiper.
Lucas - Inventor of the self-dimming headlamp.

The three-position Lucas switch--DIM, FLICKER and OFF. The other three switch settings--SMOKE, SMOLDER and IGNITE.

The Original Anti-Theft Device - Lucas Electrics.

If Lucas made guns, wars would not start either.

Back in the '70s, Lucas decided to diversify its product line and began manufacturing vacuum cleaners. It was the only product they offered which did not suck.

Q: Why do the British drink warm beer?
A: Because Lucas makes their refrigerators.