EXERCISE 14 



Growth is believed by many people to be peculiar to living things, but a very similar process is 

 sometimes found among non-living things. 



Problem. To show in non-living things a process that resembles growth in living things. 



What to use. A vessel (beaker or jar) with cover ; clean sand ; numbers of different kinds of 

 crystals, such as zinc sulfate, ferrous sulfate, copper sulfate, chrome alum, etc. ; sodium silicate (water 

 glass), i part to 10 parts water. 



What to do. Place a thin layer of sand on bottom of beaker. Place on the sand a few crystals of 

 various sizes ; pour in diluted water glass to a height of two or three inches ; cover. Put in a safe place 

 and do not disturb for six or seven days. 



Record. Note any changes that take place in the jar. 



Questions. 1. In what ways does the behavior of the things in the jar resemble that of living things? 

 2. In what ways does it differ from that of living things ? 



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