Final answer:
A red reader light and tower light often signal warning or danger, such as hazards to navigation for mariners or a crucial situation in literature. It signals to pay attention and proceed with caution, and red is a universal signal for alerting to potential risks.
Step-by-step explanation:
If the reader light and the tower light are red, this typically indicates a warning or the presence of some danger. In the context of a lighthouse, red lights can be used to signal mariners of potential hazards such as rocks, shoals, or dangerous currents near the shore. Mariners rely on these lights to navigate safely around such perils, especially at night or during rough weather when visibility is poor.
In literature, a red light might symbolize danger or a critical turning point in the plot. For example, in the passage given, the mention of a lighthouse implies a setting at sea and suggests that the characters are looking for assistance or warning from the lighthouse keeper, potentially to save them from an impending threat.
If this question refers to car headlights or any other light source, red generally signals attention or caution. It is important not to look directly at bright lights because it can harm your eyes.