COMPOSITION OF PLANTS AND ANIMALS 11 



In 



In 



Sea 



Blood 



Wafer 



Serum 



test the gas in the closed jar by shaking it with Hme water, a color- 

 less liquid/ we find that a milky white precipitate is formed. 

 This indicates the presence of a 

 gas called carbon dioxide (CO2), 

 which is formed by the union 

 of one part of carbon with two 

 of oxygen of the air. If lime- 

 water is shaken in a jar of fresh 

 air little or no precipitate will 

 be formed. Most of the car- 

 bon dioxide, therefore, must 

 have come from the burning 

 candle. 



The Composition of Plants ^ 



and Animals. — The soil and /yf /?» 



Calcium^i 



Sodium 



Potass'm 



Chlorine 



other things in nature are 

 largely composed of chemical 

 compounds, a few like water, 

 iron rust, and table salt being 

 simple, but the greater number 

 being very complex. Rocks, 

 humus, organic food sub- 

 stances, and the bodies of plants 

 and animals are all composed 

 of chemical compounds. Pro- 

 fessor H. F. Osborne of Colum- 

 bia University has pointed out 

 that the chemical substances 

 found in sea water agree very 

 closely with those in the human ^J;^^ 

 blood. There are other facts Rfomjnfi. 

 also which prove that the same 



5O4 



3059 



3.79 



5527 



Uh 



39.00 



45.0 



12.0 



Sodium 



-Ma^nesiuw 



Kdlcium 



^Potdssium 



Chlorine 



CO3 



P.Os 



0^ 



Percentages of chemical substances in sea 

 chemical elements found in the water and in blood serum. (After Osborn.) 



environment somehow or other 



become organized into the tremendously complex stuff of which 



we find living plants and animals composed. These elements 



^Limewater can be made by shaking a piece of quicklime the size of your fist in 

 about two quarts of water. Filter the limewater and keep it in bottles well corked. 



