This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1858 Excerpt: ...of the former, leaving the middle higher parts of the latter, descend gradually towards their respective anterior and posterior edges which arje situated upon a lower plane. Hence, when the face is directed to one side, the atlas is placed at a somewhat lower level than when we look straight forward; the difference ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1858 Excerpt: ...of the former, leaving the middle higher parts of the latter, descend gradually towards their respective anterior and posterior edges which arje situated upon a lower plane. Hence, when the face is directed to one side, the atlas is placed at a somewhat lower level than when we look straight forward; the difference consisting in the difference of altitude of the middle of the articular facets of the axis above their anterior and posterior marginal portions. In accordance with this, if the anterior tubercle of the atlas be observed, when the rotatory movement of this bone upon the axis is made to take place, it will be seen to describe a curve in its passage from one side to the other, the highest point of the curve being attained when it is in the mid-position. The object of this arrangement is to maintain the ligaments that connect the axis with the occiput always in a state of tension, so as to ensure the security and steadiness of these parts, which is most important, under all circumstances, and in all positions of the head. For instance, when the face is directed forwards, the atlas resting upon the most prominent portions of the axis, and the occiput being thereby distanced from the axis, the ligaments connecting these two bones, and running straight from one to the other, are quite tense. During rotation to either side, the slight increase of distance between the points of attachments of the ligaments that would be effected by the shifting of the bones is just compensated for by the approximation of one bone to the other, in consequence of the atlas sliding on to the lower parts of the articular surfaces of the axis; so that no change of distance really takes place between the points of attachment of the ligaments, and the latter remain equally tight...
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Add this copy of A Treatise On the Human Skeleton: (Including the Joints to cart. $29.16, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
Add this copy of A Treatise On the Human Skeleton: (Including the Joints to cart. $38.60, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
