He succeeded in arranging the spectral lines of helium in two spectral series and, until 1897, this was thought to be evidence that hydrogen was a mixture of two elements.
Tagumpay siya sa arranging ang linya ng multo ng helium sa dalawang multo serye at, hanggang 1897, ito ay na-iisip na katibayan na haydrodyen ay isang timpla ng dalawang elemento.