102 
MANUAL OP NATURE STUDY. 
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 pas£ 
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 villi, 
like the root hairs in the ground, suck the j uice 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. 
