Certified Interior Decorator (CID) Practice Test 2025 – All-in-One Comprehensive Guide to Exam Success!

The unsteady light produced by Roman lamps was primarily due to the absence of a chimney and the exposure to ventilation. Roman lamps, which were often open oil lamps, did not have the benefit of a chimney to direct airflow and manage the combustion process effectively. As a result, when exposed to drafts or changes in air pressure, the flame would flicker or dim, leading to inconsistent lighting.

This factor is significant because the design of the lamp directly impacts the flame's stability. Without a controlled environment, various elements such as wind or even the movement of people could disturb the flame, causing it to behave erratically.

While other factors such as inadequate wick sizes or low-quality materials could have affected the performance of the lamp, they were not the primary reason for the unsteady light. The absence of a chimney and controlled ventilation played a more critical role in the stability of the flame and the quality of light produced.