Incisions were made in the tissue of skin, muscle tendon, stomach and intestine by plain and electric knife and the state of edema was investigated macroscopically and histologically as well as concerning their water contents. 1) The measured values of water content in various tissues agreed with macroscopie and histological changes. 2) In the case of normal condition, edema followed almost the similar course, i.e. it reached to its maximum at the second day from the incision and disappeared about the second week. 3) In the skin, edema appeared and disappeared slowly but in the muscle it sirongly accelerated and quickly disappeared. In the tendon it was intermediate. The stomach and intestine took almost the same tendency but it occured faster and more in quantity in the intestine. 4) Edema was always rather more intensive in case of using an electric knife than a plain knife. 5) Under states of anoxia and hypercapnia, edema occured more slowly than in the normal case; it reached ifs maximum point at the third day and its disappear delayed generally. 6) Under the state of hypoproteinaemia, it occured faster than in the case of anoxia and hypercapnia; it reached its maximum point at the second dav and its duration was far longer, Its degree was also larger. 7) In the case of hypoporteinaemia, not only intensive edema but also a local disturdance of blood circulation was found in the stomach and intestine.