
 
        
         
		upper half of the sternum, and the corresponding costal cartilages  
 have been absorbed;  portions of the latter may  be  seen  
 projecting into the sac.  Heart, not  preserved. 
 B. c. 260.  Aorta, Exhibiting two aneurisms ;—one, situated  
 at the origin of the arteria innominata,  which partakes in the  
 dilatation;  the  other,  at  the  descending  part  of  the  arch.  
 Both  sacs  contain  numerous  patches  of  bone;  the  aorta  is  
 diseased throughout.—Professor Kirby. 
 B. c. 261.  Extensive disease of the aorta, complicated with  
 local aneurism.  The spinal column, together with  the  aorta,  
 oesophagus, part  of the diaphragm, &c.  are preserved  in  the  
 preparation.  The disease commences  with  the  origin of the  
 aorta, and extends  into  the  iliac  arteries.  The coats of the  
 vessel, throughout  this  long extent,  are  thickened,  more  or  
 less dilated, and studded internally  with  osseous  and atheromatous  
 patches.  Firm adhesions have been contracted between  
 the thoracic part of the artery and the bones of the spine.  As  
 the vessel  approaches  the  diaphragm, it dilates  into  a  great  
 fusiform aneurism,  the  lower  "end  of  w’hich  comes  near  the  
 bifurcation on the lumbar vertebrae. The cceliac and mesenteric  
 trunks spring, with open mouths, from the centre of the great  
 sac.  The  aneurism  is,  evidently,  one  of pure  dilatation,  as  
 all the textures of the original vessel are demonstrable in every  
 part of its extent.  A tubular coagulum  (see B. c. 262)  lined  
 its walls,—hollow^, down the centre, to  allow of the passage of  
 blood to the lower  extremities ;  and  presenting  apertures  at  
 the sides,  corresponding  to  the mouths  of  the  great  vessels  
 springing out  of  the  dilated sac.  The individual,  a  strong,  
 middle-aged,  and,  apparently,  otherwise  healthy  man,  was  
 brought into the  dissecting  room  for  anatomical  inspection.  
 Death had been produced by a bursting  of the aneurism into  
 the left cavity of the chest at a point where it was covered by  
 the pleura. There was a large extravasation of coagulated blood.  
 The laceration, about an inch in length, is shown.  The mitral 
 and semilunar valves were slightly thickened and opaque, and  
 the left ventricle in some degree hypertrophied, but not at all  
 in  proportion  to  the  amount  of  disease  in  the  aorta.—  
 Dr. Houston. 
 B. o. 262.  Coagulum from the aneurismal sac, shown in the  
 foregoing preparation.  It is hollow down the centre, and presents  
 apertures at the sides, for the transmission of fluid blood  
 into the vessels leading off from the dilated cavity.—Idem. 
 B. c. 263.  Aneurism of the aorta, communicating with that  
 vessel by a circular aperture, at the origin of the arteria innominata. 
   It at once swells out into a tumor, as large as a child’s  
 head, which pressed against, and caused absorption of, part of  
 the sternum, the end of the right  clavicle,  and a considerable  
 portion  of  the  three  first  ribs.  Superiorly, it ascended  into  
 the neck, compressing the trachea, and oesophagus, and giving  
 rise thereby to difficult respiration and dysphagia.  From the  
 right side of the aneurism, a secondary one arises, about  one-  
 third of its size, and united to it by a kind of neck.  The right  
 subclavian artery is stretched behind the surface of the larger  
 tumor, and its canal obliterated: the right carotid is similarly  
 circumstanced.  For several months before death, the pulse at  
 the wrist of that side could not be felt.  The sac is filled by a  
 very firm mass of fibrin.  The remainder of the aorta  is  diseased, 
  though its valves remain healthy.  The left ventricle is  
 dilated, but not hypertrophied. 
 The case was that  of an  officer, who had served  for  many  
 years  on  the  continent.  The  disease  set  in  soon  after  his  
 return home;  and  lie  attributed it to the  frequent  straining  
 induced  by  an  irritable  state  of  the  bladder.  Death  took  
 place in three years from the commencement of the affection.  
 •—Richard Carmichael, Esq. 
 '  B. c. 264.  Aneurism of the aorta.  This is a beautiful specimen  
 of that form of the disease  produced by dilatation  of all  
 the coats.  The expansion commences at the left ventricle, and