102 MANUAL OP NATURB STUDV. 



root hairs. So something must be doue. Nature 

 here again provides a remedy. This solid matter 

 must be dissolved before it can soak through the 

 walls of the stomach or be taken up by the villi. 

 See third grade work in regard to villi. So a set 

 of organs are made to manufacture solvent juices, 

 which are poured upon these solids in the stomach. 

 These juices keep pouring into the stomach until 

 the food is sufficiently softened and liquified to pass 

 out at the back door (phyloric orifice) of the stom- 

 ach into a long coiled tube called the small intes- 

 tines. Here again other solvent juices are poured 

 in until all the food that is fit for use in the body 

 is dissolved just like sugar in milk; then the vilh^ 

 like the root hairs in the ground, suck the juice up 

 and the lacteals (milk drinkers), a system of hair- 

 like tubes, carry it onward to a larger tube called 

 the thoracic duct, through which the food fluid is 

 passed into the veins, and thence through the heart 

 to general circulation throughout the body, visit- 

 ing muscles, nerves and bones, repairing the waste 

 places on the way. 



Experiment. 



1. Dissolve a small lump of limestone with 

 hydrochloric acid. Note the rapid action as the 

 limestone passes into solution. 



2. Pour a half glass full of water into the acid 

 over the limestone. Note the decrease in action. 



