Sparks.

This article from Land Rover Monthly discusses the ignition systems used in petrol-engined Land Rovers, specifically focusing on contact breaker (points) ignition. The article explains how these systems require regular maintenance and adjustment to produce a spark, and discusses the different types of distributors used in Land Rovers. It also covers the importance of ignition timing and the potential issues that can arise with the points, condenser, rotor arm, and centrifugal advance mechanism. The article concludes by mentioning the popularity of electronic ignition conversions and the availability of reproduction distributors. [Extracted from the article]