How did Savigny define possession and what are the essentials of his definition?

[Jurisprudence] -According to Savigny, the essence of possession is to be found in the physical power of exclusion. He maintained that possession is consisted of two elements, namely, corpus possessionis, i.e., physical control, and animus domini, i.e., an intention to hold as owner. Since, possession involved both these elements, the permanent loss of one or the other brought possession to an end. Savigny also thought that since the detentor and possessor have the same physical retention to the res, the difference between them should be detected in the mental element, and the intent which demarcates a possessor, is animus domini, i.e., a desire to hold for oneself and on behalf of others.