On the arrangement of the fibres of the heart / by Henry Searle.
- Searle, Henry.
- Date:
- 1838
Licence: Public Domain Mark
Credit: On the arrangement of the fibres of the heart / by Henry Searle. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![only more slender, but more numerous and in- terlaced ; in these, the interstices in many places are not filled in, the internal and external proper membranes being in contact, and thus completing the wall. Fig. 7 affords an interior view of a section of the right auricle, in which, Fig. 7. the lining membrane being removed, the fibres are seen arising from the tendinous margin of the annulus venosus av, forming the internal part of the wall of this auricle, and in their progress up arranged into columns, c, the branches of which are entwined together so as to construct the appendix. These convo- luted columns at the posterior aspect of the appendices are flattened, as shown in fig. 8, c, where their fibres are associating together, and Fig. 8. in passing round the edges to the anterior sur- face becomeevenly arranged again,as seen in the ippendix a of the right auricle, ra, of Jig. 9. I'hus far the construction of the two auricles Fig. 9. CS D agrees, the fibres of each arising from its respec tive annulus, forming first the inner part of th wall of the auricle, and then being arrange' into columns which entwine together, formin the whole of the appendix. The fibres of th right auricle, after having formed the wall c this cavity, are prolonged to form the outer pai of the wall of the left auricle. As may be see in fig. 9, the fibres which extend from the con voluted fibres of the posterior surface of tin right auricle, ra, wind evenly arranged, som over the apex, and others round the auriclf marked c, completing the outer part of the wal of the entire auricle: they then meet at th septum S, across which they pass associate* together, marked d, and on reaching the lei auricle divide into an upper portion and ai anterior and posterior band. The upperportio'. is composed of the continued fibres d, whicl proceed up the appendix and encircle its apex The anterior band e winds round the left au ricle la, and on reaching the root of thi aorta k, its fibres become more or less at tached to it in different hearts ; in its coursi upwards, marked f, when it has completed; circle it passes behind the fibres which form th' first part of the circle to enter into the formatioi of the fleshy columns of the appendix. Thij posterior band passes over the left auricle be; tween the appendix a and the vena cava su perior cs; and in fig. 8 it can be traced] coming over, marked g, and passing along tin posterior surface of this auricle la, including in its course the posterior edge of the appendi; a ; the fibres which pass along the posterio: edge of the appendix, on arriving at the ante rior edge, separate from the band g to pursue their course round the edge of the appendix,— now along the anterior edge,—and join the fibres d, which cap the apex. This divisioi of the band which encircles the appendix is com stant, and evidently affords particular strengtl to its edge. The band itself g winds dowr towards the base, expanding and surrounding the orifices of the pulmonary veins p; somt of its fibres become lost on the surface of the auricle, and the others may be traced totherooi of the aorta. This band cannot be completely detached ir consequence of some of its fibres being inter woven with its subjacent fibres. The left auricle, without the addition of these bands, would nearly balance in substance anc strength the right; their addition gives, there- fore, to the left a considerable preponderance in these respects over the right auricle. The septum S is, in fig. 9, shown to be com- posed, superiorly, of the transverse band of fibres d, which passes from the right to the left auricle; in its middle part, of the ascending fibres h, which arise from the root of the aorta k, and pass up behind the band d, some](https://iiif.wellcomecollection.org/image/b22386476_0015.jp2/full/800%2C/0/default.jpg)
