- Author
-
Mulholland, G. W.
- Title
- Natural Phenomena Pertaining to Small Particles. Undergraduate Lecture Series for Science University of Tokyo.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Keywords
-
particles
|
smoke detectors
- Identifiers
- Einstein's theory of Brownian Movement; proof of the existence of molecules
- Abstract
- Before discussing Einstein's theory, it is appropriate to describe Robert Brown's contribution to the understanding of the phenomenon that bears his name. The so called "Brownian movement" was described for the first time in the year 1828, by the Scothis scientist, Robert Brown. He was interested in the mode of action of pollen in the process of impregnation and sought species having irregularly shaped rather than spherical pollen grains in order to trace their movement to the ovum more easily. Granules extracted from the pollen of Clarckia pulcella seem suited for this purpose, and it was while examining the shape of these particles immersed in water with a simple microscope that Brown noted their rapid irregular movements. He observed that these "arise neither from currents in the fluid, nor from its gradual evaporation, but belonged to the particle itself."