Something like the boiling wand was available in the 1950's in the US. It had the heavy coil that was immersed in the liquid but was bent so as to hang over the

Something like the boiling wand was available in the 1950's in the US. It had the heavy coil that was immersed in the liquid but was bent so as to hang over the lip of a cup or mug. My parents made their morning (instant) coffee with one on vacations. Blazingly hot and had to be watched closely...