207 



ENLARGEMENT OF THE HEART AND ITS CAVITIES. 



Leblanc has published some ' Recherches^ on the Dis- 

 eases of the Heart of the principal Domestic Animals/ 

 commencing by what he calls completing the anatomy of 

 the hearty by taking the dimensions of its various parts ; 

 and afterwards studying the anatomical characters of its 

 lesions in a great number of animals. 



In a mare 15 hands high, from 10 to 12 years old, he 

 found the walls of the left ventricle to be 1*5985 inches, 

 and the thinnest part of those of the right to be -5985 ; 

 and that the capacity of the left ventricle amounted to 10 

 cubic inches, and its interior surface to 26 square inches 

 (English). He found the relations between the heart and 

 the size of the animals too variable to pretend to draw any 

 comparisons between the two. In taking measure of the 

 heart, he has adverted to its being either hot or cold at the 

 time, because the hearts of animals a few hours after death, 

 and of such as are still warm, are more voluminous 

 than such as have been dead twenty-four or forty-eight 

 hours. In horses (two entire and five not), he found the 

 weight of the heart to range between little more than 41bs. 

 to nearly 91bs. ; the thickness of the right ventricle to 

 range from 0*009 to 0*044 of a metre,^ that of the left ven- 

 tricle from 0*035 to 0*052 ; of the right auricle from 0*008 

 to 0015; of the left auricle from 007 to 0*018; and that 

 of the septum cordis from 0*032 to 0*042. 



Almost all the lesions of the heart found in man are to 

 be met with in horses ; and they exist in the ratio of about 

 l-20th, according to Leblanc^s computation, — one made on 

 150 animals, comprising horses, oxen, and sheep, all whose 

 hearts he had carefully examined within the space of a 

 couple of years : it being understood that all diseases, both 

 cardiac and pericardiac, were taken into the reckoning. 



' ' Resume de quelques Recherches, relatives a I'etude des Maladies du Coeur 

 des Animaux Domestiques,' par H. Leblanc. 1840. 

 * A French metre is 39-37100 of an English inch. 



