Anatomy, descriptive and applied / Henry Gray. A new American from the 18th English ed., thoroughly rev. and re-edited, with the Basle anatomical nomenclature in English, by Robert Howden.

  • Gray, Henry, 1827-1861.
Date:
1913
Catalogue details

Licence: Public Domain Mark

Credit: Anatomy, descriptive and applied / Henry Gray. A new American from the 18th English ed., thoroughly rev. and re-edited, with the Basle anatomical nomenclature in English, by Robert Howden. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    Each canal contains one or two bloodvessels, with a small quantity of delicate connective tissue and some nerve filaments. In the larger ones there are also lymphatic vessels, and cells with branching processes which communicate, through the canalculi, with the branched processes of certain bone cells in the substance of the bone. Those canals near the surface of the bone open upon it by minute orifices, and those near the medullary cavity open in the same way into this space, so that the whole of the bone is permeated by a system of bloodvessels running through the bony canals in the centres of the Haversian systems. The lamellae are thin plates of bony tissue encircling the central canal, and may be com- pared, for the sake of illustration, to a number of sheets of paper pasted one over another around a central hollow cylinder. After macerating a piece of bone in dilute mineral acid, these lamellae may be stripped off' in a i?^ Fig. 30!—Section parallel to the surface from the body of the femur. X 100. o, Haver- sian canals; 6, lacunse seen from the side; c, others seen from the surface in lamelte, which are cut horizontally. Fig. 31.—Perforating fibres, human parietal bone, decalcified. (H. Miiller.) a, perforating fibres in situ; b, fibres drawn out of their sockets; c, sockets. longitudinal direction as thin films. If one of these be examined with a high power of the microscope, it will be found to be composed of a finely reticular structure, made up of very slender transparent fibres, decussating obliquely; and coalescing at the points of intersection; these fibres are composed of fine fibrils identical with those of white connective tissue. The intercellular matrix between the fibres is impregnated by calcareous deposit which the acid dissolves. In many places the various lamellse may be seen to be held together by tapering fibres, which run obliquely through them, pinning or bolting them together; they were first de- scribed by Sharpey, and were named by him perforating fibres (Fig. 31). The Lacunae are 'situated between the lamella, and consist of a number of oblong spaces. In an ordinary microscopic section, viewed by transmitted light, they appear as fusiform opaque spots. Each lacuna is occupied during life by a branched cell, termed a bone-cell or bone-corpuscle, the processes from which extend into the canaliculi (Fig. 32). The CanalicuU are exceedingly minute channels, crossing the lamella?_ and con- necting the lacunge with neighboring lacuna? and also with the Haversian canal. From the Haversian canal a number of canaliculi are given off, which radiate from it, and open into the first set of lacunae between the first and second lamella. From these lacuna? a second set of canaliculi is given off; these run outward to the