text: The form of the Kelvin equation here is not the form in which it appeared in Lord Kelvins article of 1871.  The derivation of the form that appears in this article from Kelvins original equation was presented by Robert von Helmholtz (son of German physicist Hermann von Helmholtz) in his dissertation of 1885. In 2020, researchers found that the equation was accurate down to the 1nm scale.