This field shows the bone marrow cavity (below) and the skeletal muscle along the external surface of the bone shaft (top right).
The eosinophilic bone tissue is composed of osteocytes and of an intercellular matrix forming lamellae. This matrix is composed of collagen (type I) associated with calcium apatite crystals.

Subjacent to the periosteum seen at the surface of the bone and of the endosteum facing the bone marrow, several concentric bone lamellae form the outer and inner circumferential lamellae.

In the rest of the compact bone, the bone lamellae are concentrically arranged around central canals (Haversian canals) containing blood vessels in a loose connective tissue. These cylindrical units, called osteons, are not too clear at this low power but will become more evident at a higher magnification further on. These osteons are parallel to the long axis of the bone. Their central canals communicate with each other via lateral branches. Some of these connections reach the bone marrow cavity.

Compact adult bone undergoes continual rearrangement owing to the dissolution and reconstruction of osteons. An area of bone resorption is visible on the right.

Stain: H–­­E
Magnification: ×100