vinal] NATURE-STUDY IN RHODE ISLAND 259 



If I pour a little water into this U-shaped glass tube the liquid 

 comes to the same height on each side. This illustrates the old 

 axiom that water seeks its own level. It seems to be a contradic- 

 tion, however, to another equally familiar adage that water will 

 not run up hill. It is valuable to know that a U-shaped pipe from 

 a spring will carry water as high in the house as the elevation of 

 the spring. Other related uses of the knowledge are pumps, water 

 supply system for the city or for a country home, sources of water 

 in wells and springs, contamination of well water, plumbing, bar- 

 ometer, vacuum cleaners, syringe, fountain pen fillers, drainage, 

 the siphon, etc. 



The class is now ready for project work. The previous lessons 

 have been suggested to some pupils as actual problems, the solu- 

 tion of which has become a personal necessity. It may be bad 

 odors due to poor plumbing; dirt in the well water; conveying 

 gasoline from a barrel to a motor boat, etc. Let them tend to 

 these new needs which have been suggested. If some one has a 

 pump at home and wishes to know how it works let him investi- 

 gate. Pupils interested in drawing could take one of these prob- 

 lems : a map to show the -city water system ; diagram of the water 

 pipes and connections in his own home; diagram of a force pump; 

 sketch of a plan to bring water from a hillside spring to a home. 

 Other lines of investigation might be irrigation; current events, 

 such as found in the following magazines : World's Work, Popular 

 Mechanics, Scientific American, Harper's Magazine and St. Nich- 

 olas, or if of a historic liking, the "Aqueducts of Rome." Each 

 one of the class should choose at least one topic. 



The class work would consist of reports, explanation of charts, 

 and trips for investigation. Some reports will be handed to the 

 teacher in writing and others will be given orally before the class. 

 This brings in a need of good language. How the subject shall be 

 presented depends upon the needs of the class. If the class is in 

 the city, every pupil should know certain things about plumbing. 

 For example, there is a U-shaped pipe beneath the sink. As it is 

 this shape it always holds a little water and this forms a sort of 

 seal which prevents the foul gases coming from the sewer into the 

 house. Sometimes grease and filth collect in this trap and it should 

 be cleaned by pouring in hot water and a disinfectant. This also 

 gives a reason for rinsing the bowl after washing, which is not us- 

 ually thought of, i. e., to remove the dirty water in the trap. Such 



