UK ART. 



585 



rendered it more complicated. We will find 

 that considerable ditlerences in these respects 

 nay exist between different hearts and between 

 different parts of the same heart, which, to 

 judne from the perfect regularity with which all 

 Us functions proceeded before death, must be 

 considered as perfectly healthy ; and it is from 

 this want of uniformity in the different parts of 

 apparently healthy hearts that we can in some 

 measure account for the discrepant statements 

 on this subject which exist in the works of the 

 most celebrated and accurate anatomists. 



Tliickiirss <_>/' Mr iculls of the several cavities 

 iif the. limrt. The left auricle is somewhat 

 thicker than the right, and the left ventricle 

 very considerably thicker than the right. Bouil- 

 laud* found the average thickness of the walls 

 of the left auricle in four healthy hearts to be 

 1J lines, and that of the right auricle to be 

 1 line. Lobstein has rather strangely staled 

 that the right auricle is twice the thickness 

 of the left. He makes the thickness of the 

 right auricle to be 1 line, and that of the left 

 to be only } line. Laennec reckons the relative 

 proportion of the thickness of the left ventricle 

 to the right as rather more than 2 to 1. 

 liouillaud found the average thickness of the 

 right ventricle at its base in a great number 

 of cases to be 2J lines, and that of the left 

 ventricle at the same part to be 7 lines. 

 Cruveilhierf states the proportionate thickness 

 of the right to the left ventricle as 1 to 4, 

 or even as 1 to 5. According to Soemmerring,j 

 the relative thickness of the two ventricles 

 is as 1 to 3. Amlnil states that in the adult 

 the thickness of the left to the right ventricle 

 is as 2 to 1, but in infancy and in old age 

 it is as 3 or 4 to 1. 



M. Bizot has lately published the results 

 of the careful measurements of the healthy 

 heart in one hundred and fifty-seven indivi- 

 duals of all ages. || The greater part of these 

 observations were collected at La Piti6, under 

 the auspices of Louis. According to M. Bizot, 

 the heart goes on increasing in all its dimen- 

 sions length, breadth, and thickness up to 

 the latest periods of life. The growth is, 

 however, more rapid before twenty-nine years 

 than after that age. While, then, the muscles 

 of animal life are diminishing in size in ad- 

 vanced life, the heart is still increasing in 

 bulk. The heart of the male is, on an average, 

 larger than that of the female at all the different 

 .-tai;es of life. M. Bizot remarks that the 

 longitudinal section of the left ventricle is 

 fusiform, the thickest part being situated at 

 the junction of the superior third with the 

 middle third .1[ The thickness of this ventricle 

 goes on increasing from youth up to advanced 

 age. The following are a few of the measure- 



* Traite Cliniquc dcs Maladies du Cotur, t. i. 

 p. 53. 1835. 



t Anatomic Descriptive, t. iii. p. 17. 



i DC Corporis Humani Fabrica, t. v. 



$ Anatomic Paihologique, t. ii. p. 283. 



|| Mi-moires de la Societe Medic. d'Observation 

 d,- 1'aris, t. i. p. 262. 1836. 



f Op. cit. p. 269 and 204. 



ments of the thickness of the walls of the 

 ventricles given by M. liizot. 



Left veiitricli; iimlr. 

 Age. Base. Middle prt. Apex. 



1 to 4 years .... 3 lines. 2ft lines. 1-fl, line. 

 50 to 7<> MM . . 4jj 5Jj 4^, 

 A.eiu'.'e from 16 ) ... ,, .,.. 



to 79 years .. i 4 > " 5 * " * 



Left ventricle, female. 



1 to 4 years .... 2ft lines. 2J lines. 2^ s lines. 

 50 to 89 years . . 4J 5 3| 

 Average from 16) ., .. _ u 



to 89 years . . 4J " l " 



Thickness of right ventricle. The thickest 

 portion of the right ventricle is not placed, 

 as M. Uizot remarks, at the same point as 

 in the left. In the right ventricle it is at the 

 base of the heart, 4 lines below the tendinous 

 ring. The thickness of the walls of the right 

 ventricle, unlike the left, remains more nearly 

 stationary at the different periods of life. They 

 are, however, a little thicker in advanced age 

 than at an earlier period of life. 



Right ventricle, male. 

 Age. Base. Middle part. Apex. 



1 to 4 years .... ? line, ft line, ft line. 

 30 to 49 years .. 1JJ 1 Jj 

 50 to 79 years .. 2y 9 1$,, Ii 

 A verasre from 16)-. , , 



to 79 years ..J 1 *" ** " '* " 

 Rig/it ventricle, female. 



1 to 4 years 1^, line. J line. JJ line. 



30 to 49 years .. IJf 1JJ ft 

 50 to 79 years . 1\ 1J 1 

 Average from 15) .. , 



to 59 years . . J " * " " 

 Care was taken to make all these measure- 

 ments at points where there were no columnx 

 carneae. 



The thickness of the septum ventriculorum, 

 according to Meckel, is 1 1 lines at its base. 

 Bouillaud obtained the same results in the 

 only case in which he appears to have measured 

 the thickness of the septum. M. Bizot has 

 given measurements of the ventricular septum 

 at six different periods of life, from which I 

 have selected the following. 



Mule. Female. 



Age. Middle part. Middle part. 



1 to 4 years 3,!, lines. 2j lines. 



16 to 29 years.... 4tf 4\\ 



50 to 79 years.... 5J 5$ 



The thickness of the septum ventriculorum 

 goes on increasing in thickness from infancy 

 to an advanced period of life. 



Relative capacities of the several cavities. 

 The most conflicting statements exist upon 

 this point, and we find it perfectly impossible 

 to come to any satisfactory decision. Each 

 cavity of the heart is supposed, when mo- 

 derately distended, to contain rather more than 

 two ounces of fluid. The auricles may be 

 safely said to be of less capacity than the 

 ventricles; and this disparity is strikingly 

 marked in the larger animals, as the horse 

 and ox. The right auricle is generally allowed 

 to be larger than the left, and the difference, 



