Reproduced from Jean Baptiste Perrin, "Mouvement brownien et réalité moléculaire," Ann. de Chimie et de Physique (VIII) 18, 5-114, 1909 (a slightly different version appeared in the book Les Atomes). Three tracings of the motion of colloidal particles of radius 0.53 µm, as seen under the microscope, are displayed. Successive positions every 30 seconds are joined by straight line segments (the mesh size is 3.2 µm)
J. B. Perrin, SVG drawing by <a href="https://en.wikipedia.org/wiki/User:MiraiWarren" class="extiw" title="en:User:MiraiWarren">MiraiWarren</a>
1909
SVG drawing based on <a href="https://en.wikipedia.org/wiki/File:PerrinPlot2.gif" class="extiw" title="w:File:PerrinPlot2.gif">File<i><b>:</b></i>PerrinPlot2.gif</a>, itself from J. B. Perrin, "Mouvement brownien et réalité moléculaire," <i>Ann. de Chimie et de Physique</i> (VIII) 18, 5-114 (1909).