To　know　the　complicate　character　of　bone　material,　which　is　anisotropic　and　non-homogeneous,　three-point-bending　tests　were　performed　in　wet　and　dry　environments　on　mini　bone　samples　which　were　cut　in　different　directions,　and　load-flexibility　curves　were　obtained.　The　bridging　phenomena　were　recorded　by　optical　microscopic　digital　video　at　the　same　time.　And　two　types　of　fiber　bridging　in　between　the　side　wall　of　the　crack　were　observed.　One　of　which　is　directly　made　of　Haversian　lamellae　in　cortical　bone,　and　the　other　type　is　of　large　number　of　fibrils　of　collagen,　in　different　diameters　of　assembling　scale.　The　method　provided　in　this　paper　is　very　useful　for　analyzing　the　biomechanical　characteristics　of　bone　material　in　detail.