Good afternoon people (or good morning). I am really curious about who was the first one to define the **gyromagnetic ratio** $\gamma$ of a body, i.e., the ratio of its magnetic dipole momento to its angular momentum.

It is a very important concept in Quantum Mechanics, but I was wondering whether it first appeared in a classical context or in a quantum one, who defined it, and why?

We can see it appears in the formula for the Larmor precession:
$$
\omega=\gamma B \hspace{100pt} (1)
$$
which tells us the frequency of precession of a body in the presence of a magnetic field $B$. Was Larmor the first person to highlight the importance of this ratio? was he the first one that used it in a formula? was $(1)$ the first formula where $\gamma$ appeared? If he was indeed the first one, could you tell me what was the name of the paper in which he published the results?


Thank you for your help!!