What was required to immerse the early string galvanometers for stable readings?

Answer

water

The early string galvanometers, vital components of Willem Einthoven's initial ECG setup, required immersion in water to achieve stable readings necessary for accurate electrical recording. This necessity underscores the environmental sensitivity of the technology available in the early 1900s. The requirement for water immersion acted as a crucial dampening mechanism, helping to stabilize the sensitive instruments against environmental noise and vibration, which was a major limiting factor when compared to modern electronic shielding techniques.

What was required to immerse the early string galvanometers for stable readings?
inventiondeviceECGcardiograph