The establishment of a law, moreover, does not take place when the first thought of it takes form, or even when its significance is recognised, but only when it has been confirmed by the results of the experiment.

I saw in a dream a table where all the elements fell into place as required. Awakening, I immediately wrote it down on a piece of paper.

Elements which are similar as regards their chemical properties have atomic weights which are either of nearly the same value (eg. Pt, Ir, Os) or which increase regularly (eg. K, Ru, Cs).

No law of nature, however general, has been established all at once; its recognition has always been preceded by many presentiments.

There exists everywhere a medium in things, determined by equilibrium.

When the elements are arranged in vertical columns according to increasing atomic weight, so that the horizontal lines contain analogous elements again according to increasing atomic weight, an arrangement results from which several general conclusions may be drawn.

The establishment of a law, moreover, does not take place when the first thought of it takes form, or even when its significance is recognised, but only when it has been confirmed by the results of the experiment.