LIVER. 



system, and there it is that the richest treasures of the 

 vegetable kingdom are spread out in the most generous 

 profusion. The slaves in our southern plantations whose 

 diet consists entirely of Indian corn, continue in much 

 better condition and are capable of performing a greater 

 amount of labour, than those whose masters allow them 

 a quantity of animal food, and who on the contrary are 

 weak, drooping and sickly. We will now follow up the 

 changes which the food undergoes in its passage into the 

 system. 



Emily. Having been fully converted into chyme, 

 I presume it passes on into the intestinal canal. I can- 

 not imagine what else can happen to it before it is pre- 

 pared for the purposes of nutrition. 



Dr. B. Now commences the second stage of diges- 

 tion, or that of chylifaation, which is produced chiefly 

 by means of the various fluids that are poured out and 

 mixed with the food. Our next step then will be to ex- 

 amine the qualities of these fluids and the organs by which 

 they are secreted. The most important of them is the 

 bile, a slightly viscid, bitter, and yellowish fluid of a very 

 compound nature, being at once watery, albuminous, 

 oily, alkaline and saline. The liver by which it is se- 

 creted, is the largest viscus in the whole body. It is 

 situated on the right side in the upper part of the afydo- 

 men, and is fixed firmly in its place by several strong 

 ligaments which attach it to the diaphram. Its surface 

 is concave on one side and irregularly convex on the 

 other, and is divided into several lobes by deep fissures. 

 What renders the construction of the liver peculiarly 

 remarkable is, that while like other organs it has its prop- 

 er arteries and veins, it has unlike any of them another 

 arid a complex system of veins. It is called the vena 

 portce ; the proper vessels of the liver are called hepatic 

 artery and hepatic veins. The vena portae is formed af- 

 ter the following manner : all the veins which carry 

 back the blood from the intestinal canal, stomach, spleen 



