How high can the temperature of a liquid be raised without boiling?

How high the temperature of a liquid can be raised beyond its boiling point without vaporizing (known as the limit of superheat) is an interesting sub ject of investigation. A different method of finding the limit of superheat of liquids is presented here. The superheated liquids are taken in the for m of drops suspended in a dust free gel. The temperature of the superheated liquid is increased very slowly from room temperature to the temperature a t which the liquid nucleates to boiling. The nucleation is detected acousti cally by a sensitive piezoelectric transducer, coupled to a multichannel sc aler, and the nucleation rate is observed as a function of time. The limit of superheat measured by the present method supersedes other measurements a nd theoretical predictions in reaching the temperature closest to the criti cal temperature of the liquids.