A circular chart recorder:

A circular chart recorder employs a bourdon tube as part of its design, which is essential for measuring pressure. The bourdon tube is a flexible, curved metal tube that expands when pressure is applied, causing a pointer or stylus to move across the chart. This movement inscribes a continuous record on the circular chart, allowing users to visually gauge fluctuations in pressure over time.

In contrast, while a strip chart recorder also provides a graphical record of measurement, it typically uses a different mechanism for recording data and presents it in a linear format. The choice of a circular chart recorder highlights its specific application in environments where space constraints and the need for a continuous, cyclical record are prevalent. Therefore, its integration of a bourdon tube is a key feature that differentiates its functionality, making it particularly suitable for displaying data like pressure readings in a compact and accessible manner.