Final answer:
The question about the maximum boiler horsepower for a chief engineer license is more related to regulatory aspects than the direct operation of steam engines. However, chief engineers must understand the principles of engine efficiency, such as the Carnot cycle. Typically, a chief engineer license could allow taking charge of boilers with unlimited horsepower.
Step-by-step explanation:
When discussing the maximum boiler horsepower a chief engineer may take charge of on a chief engineer license, it's important to note that this question does not pertain directly to actual steam engine operation but rather licensing and regulatory requirements. However, the information given about practical steam engines and temperatures can indirectly relate to engineering knowledge required by a chief engineer.
For steam engines, the maximum theoretical efficiency is determined by the Carnot efficiency, which is a function of the temperatures at which the engine operates. This efficiency is calculated using the temperatures in Kelvin, where the efficiency (η) is η = 1 - (Tc / Th), with Tc as the cold reservoir temperature and Th as the hot reservoir temperature.
A chief engineer would be expected to understand these principles as part of his or her competencies. Regarding the specific answer to the licensing question, typically, licensing for boiler horsepower is not limited to a defined maximum such as 100 or 500 horsepower but varies by jurisdiction. In many places, a chief engineer license may allow a professional to be in charge of an facility with unlimited horsepower.