EXERCISE 23 



Problem. Has air anything to do with the sprouting of seeds ? 



What to use. Seeds that have been soaked overnight (pea, bean, or maize) ; vessels that can be 

 sealed air tight ; sand. 



What to do. Place groups of seeds ready to sprout in situations having varying quantities of air. 

 This can be done by using vessels of the same size and equal numbers of seeds, displacing air by 

 means of sand (as shown on left side of diagram), or by using same-sized bottles and varying number 

 of seeds. Have experiment tried in different ways by parts of the class. 



Place all bottles in same place ; make observations twenty-four hours apart. 



Record carefully all changes by words or pictures. 



Conclusion. What has the amount of air to do with sprouting ? 



Question. How can you tell that the differences in result were not due to factors other than air ? 



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