A Frenchman, Leon Edoux, developed the first what type of hydraulic elevator?

Leon Edoux developed the first direct hydraulic elevator, which uses a hydraulic cylinder to raise and lower the elevator car directly. In this system, pressurized fluid is applied directly to the piston, allowing for a straightforward and efficient lifting mechanism. Direct hydraulic elevators are known for their ability to handle heavier loads at lower heights, which aligns with Edoux's innovative contribution to elevator technology.

Pneumatic elevators, while noteworthy in their own right, work on a different principle utilizing air pressure. Indirect hydraulic systems often involve mechanisms that transfer the hydraulic pressure indirectly, which can add complexity and lower efficiency for certain applications. Traction elevators operate by using a system of ropes and pulleys, fundamentally different from the direct hydraulic approach. Understanding these distinctions clarifies why Edoux's direct design was a significant advancement in elevator technology.