148 ASSIMILATION AND ITS ORGANS. 



food of the mouth is the freest, comprising the particles which only 

 require the moving opportunity offered by the teeth and the tongue, 

 to quit their former attachments in the substance they belonged to, 

 and to rise at once into the new society whither they are bound. 

 They put off their bodies with nimble ease, and are presently at 

 home among the particles and occupations of the human form. 

 The grosser molecules never miss them, or know how they go in, or 

 whither they have gone. The most living saliva, wing-footed as 

 Mercury, spirits them in by the secret paths which it has trodden 

 perhaps often, and of its own nature knows so well. 



The food of the stomach, immeasurably more bulky, and subject 

 to greater and longer probations, yet passes immediately into the 

 hungry blood : the little veins which stand open-throated on every 

 portion of the distinctly ventriculated surface, carry crowds of these 

 slower individuals into the bosom of the abdominal circulation. The 

 alimentary mass reduced into chyme in the stomach, yields its re- 

 luctant vintage directly to the blood. The possibility of an imme- 

 diate reception of the food by the blood, appears for the most part 

 to end with the stomach ; the way for the next order of particles is 

 long and difficult, and the preparation corresponding. Beyond the 

 stomach a lower order of vessels than the veins receives the food, 

 namely, the lacteals; there is an intermediate school between the 

 food and the blood, namely, the chyle. These lac teals arising from 

 the alimentary tube, but decreasing in number in its lower parts, 

 where there is less of the milky chyle to absorb, converge from the 

 intestines to the receptacle of the chyle, a small reservoir seated in 

 front of the lower vertebras; this reservoir is then continued up- 

 wards in a fine pipe called the thoracic duct, and runs all the way 

 to the left side of the neck, where it runs into the fork of a great 

 vein that pours its blood directly into the right side of the heart. 

 A long passage for the chyle, contrasted with the short cut which 

 the higher portions of the food enjoy, to their desired haven in the 

 blood ! "We infer from this, the comparative imperfection of the 

 chyle, vexed as it is with such abundant trials, and ultimately let 

 in through the intervention of a peculiar saliva, termed the lymph. 

 This lymph is brought by the lymphatics from all parts of the frame 

 to the same receptacle and duct : it is the old spirit of the blood 



