VOL. XXVII.] PHILOSOPHICAL TRANSACTIONS. 57^ 



transverse processes of each vertebra and its body, throughout the whole 

 spine, for transmission of the several conjugations of nerves from the spinal 

 marrow. 



The fifth vertebra is of the same dimensions with the other two, and differs 

 in nothing from them but by its spinal process, which, from 4- inch in the for- 

 mer, rises to I4 in this, being 4- inch broad, and thin at the extremity. The 

 sixth vertebra differs from all the rest in its transverse process, which is as far 

 forward as the rest, and sends out another process, which runs as backward ; so 

 that from the extremity at the fore part to that at the back part, it is 3 inches. 

 It also sends another protuberance obliquely outward 14- inch. At this process 

 the cervical artery passes out from the transverse process of the vertebra, and 

 only sends a twig to the seventh vertebra, or last of the neck, which differs 

 from all the rest, 1st. In the length of its spinal process, which is augmented 

 from 3 inches in the former to 5 in this. 2. In the smallness of the hole for 

 the cervical artery, this being the last perforated transverse process, as is said, 

 3. In a sinus on each side of its body behind, into which it receives part of the 

 first rib. 



The thorax is divided into the vertebras, ribs, and sternum : there are 1 Q 

 vertebrae, correspondent to so many pair of ribs ; they differ in nothing from 

 the former, except that their body is more protuberant, that their spinal pro- 

 cesses are augmented, and diminished in their length, according to their situa- 

 tion, and that they have a sinus in each side, both before and behind, for the 

 reception of their respective ribs : for the weight and dimensions of their spinal 

 processes see the following table. 



The ribs are divided into the true (which are articulated with the sternum) 

 and false ones, with, and without cartilages. There are 8 pair of true ribs, 8 

 pair false with, and 3 without cartilages. The cartilages here are soft, as in 

 human subjects, and not bony as in oxen, harts, &c. 



The sternum consists of four bones ; they are placed edgewise, being two 

 inches thick above, and sharp below : from the fore part to the point of the 

 cartilago ensiformis it is 25 inches ; of which the first is 8 inches long, and 44- 

 inches broad at the articulation of the first rib ; the second 44 inches long, and 

 3 inches broad ; the third 34- inches long, and 3 inches broad; the 4th 4 inches 

 long, and 24 inches broad ; the rest of the length is made out by the cartilago 

 ensiformis. 



The loins consist of three vertebrae, whose spinal processes are but short ; 

 their transverse processes a little longer than those in the back; which, besides 

 their weight, is all that is material about them. 



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