ARRHENIUS, SVANTE AUGUST one of the founders of the modern science of physical chemistry, was born on Feb. 19, 18J9, at the castle of Wijk, near Uppsala in Sweden. The family name derives from the property of Arena. As a young child he showed an extraordinary facility in calcu lating, and at school distinguished himself by his mathematical ability. At the age of 17 he entered the University of Uppsala, devoting himself to physics in particular, but, finding that the practical instruction in physics there left something to be desired in those days, in 1881 he went to study under Edlund at Stock holm. In 1884 he took his doctor's degree at Uppsala with a thesis entitled Recherchies sur la conductibilite galvanique. This thesis, which later earned for Arrhenius the Nobel prize, was awarded the lowest "note" which could be granted without a definite refusal. It is divided into two parts, the first dealing with the experimental determination of the electrical conductivity of extremely dilute solutions, and the second with the theory of elec trolytic conductivity. This second part expounds his theory of electrolytic dissociation and activity co-efficients (see ELEC