His eyesight being now restored, he began work again as soon as he arrived. This period, however, was not a pleasant one: to begin with, he obtained in the study of Ascidia a result which differed considerably from that obtained by Kovalevsky,[11] and this scientific controversy grieved and preoccupied them both. Besides, Elie's nerves suffered from his constant anxiety about his eyes, the tropical heat and the noisy life of Naples. Incessant serenades used to keep him awake at night, and, on one occasion, his exasperation reached such a point that he poured a bucket of water over the head of some persistent musicians. Tired with all these things, he left Naples for Trieste, where he carried out successful researches into the transformations of Echinodermata, from the point of view of Comparative Embryology and genetic connections between inferior animals. [11] The latter affirmed that the nervous system of Ascidia originated from the upper layer, whilst Elie believed that it was the lower layer which gave birth to it. It was Kovalevsky who was right, as Elie himself declared later. Having obtained results which interested him, he returned to Russia and joined the B. family in the country, near Moscow. Their young friend Mlle. Fédorovitch, whom he had already met in Petersburg, was staying with them, and she and Elie became very good friends. His affection for the B. children led him to ponder over general educational questions. He was struck for the first time by the lack of harmony in human nature, which was due, he thought, to the considerable difference between the organism of the child and that of the adult, a difference which does not exist in animals to the same degree.[12] As soon as he returned to Petersburg he tried to study this subject, and made comparisons between the brain of a man and that of a dog at various ages, but without result. [12] He ultimately developed these considerations in a paper entitled _Education from an Anthropological Point of View_, of which mention will be made hereafter.