48 LABORATORY LESSONS IN GENERAL SCIENCE 



tive fluids? About what per cent of the blood is water? 

 What purposes are served by having this so? 



5. Explain somewhat at length how the various cells 

 of the body get their nourishment, and how they get rid 

 of their waste products. When this waste matter gets 

 into the blood, how is it disposed of ? Do the red corpuscles 

 of the blood pass through the walls of the blood vessels? 

 What is true of the white corpuscles? 



6. What part does the solvent power of water play in 

 the nourishment of plants? What part has osmosis? In 

 the growing plant evaporation from the leaves (transpira- 

 tion) rids the plant of relatively large volumes of its sap 

 water. What part may this have in the rise of sap through 

 growing plants? 



STUDY OF A STREAM 



1. Mention by name (or locate otherwise) the creek, 

 brook, or river nearest to the school building. How far 

 is it from the school (a) by highway; (b) by most direct 

 route ? Are there fish in its waters ? - If so, what kinds ? 

 If not, why not? 



2. What is true of the rate of its current at different 

 places? In general is the current swift or sluggish? How 

 could you determine quite accurately just how swift it is 

 at any point?' Why is it not swifter? Account for the 

 direction of its flow. 



3. Describe the course of the stream so far as it is known 

 to you, telling whence it comes, the general direction of 

 its flow, and what becomes of its waters. Upon what does 



