# How was the Kelvin Scale created?

How was it found that if we go $$\rm 273°C$$ below $$0$$, we would reach absolute zero. What experiment gave this result.

Charles' law states that :

Volume is directly proportional to the absolute temperature.

Was the Kelvin perhaps created as scale in which temperature and pressure of a gas are proportional?

I tried to find absolute zero in this manner with experimental data from this video.

This is my work:

$$v_1$$ $$= \rm 112\ mL$$

$$t_1$$ $$= \rm 23°C$$

$$v_2$$ $$= \rm 138 \ mL$$

$$t_2$$ $$= \rm 100°C$$

Let's define $$x$$ as the quantity to add to °C measurement's to satisfy Charles' law. In other words $$\rm -x°C$$ would be absolute zero.

$$\begin{equation} \frac{v_1}{v_2} = \frac{x + t_1}{x + t_2} \\ \frac{112}{138} = \frac{x + 23}{x + 100} \\ 26x = 112×100 - 138×23 \\ x = 308.69 \end{equation}$$ I also tried other values but I am not getting the desired answer. Is there a flaw in my reasoning or does this have nothing to do with the Kelvin scale at all? If so, then how was the Kelvin scale formulated.