TOOLS WITH WHICH WE WILL WORK 21 



20. To learn how my coal range is constructed and how to run it. Page 189. 



21. To remove the fire hazards from my home. Page 205. 



22. To find out what my clothes are made of. Page 219. 



23. To improve the lighting in my home. Page 238. 



24. To remedy any eye defects I may have. Page 253. 



25. To plan an ideal house. Page 267. 



26. To become a landscape gardener for my own home. Page 286. 



27. To learn the soil needs in my garden for any particular crop. Page 297. 



28. To eliminate the plant pests from my home grounds. Page 314. 



29. To keep the machines of the home in good working condition. Page 33 1 . 



30. To install an electric bell in my home. Page 344. 



31. To install a night light in my bedroom. Page 359. 



32. To understand the mechanism of the piano and the piano player. Page 



37i- 



33. To plan how to utilize the playgrounds of the home lot. Page 390. 



Tools with which we will work. A notebook in which to 

 make careful notes of all work done is an essential part of 

 our equipment. We should always take notes of every- 

 thing we do, both in the laboratory and at home. These 

 notes should be carefully kept, and drawings made to illus- 

 trate them, either with a hard pencil or with a drawing pen. 

 We must learn to use instruments with which to measure. 

 The use of the metric system is best for all scientific meas- 

 urements, and a knowledge of the metric tables will be 

 found valuable. We must also know how to use a com- 

 pass and a T-square, and other instruments useful in diagram 

 making. Perhaps the most essential thing of all is to learn 

 the value of accurate figures, as this is needful in the mak- 

 ing and understanding of graphs. A graph is the diagram- 

 matic representation of a certain number of figures. An 

 example is seen in the diagram on page 22, in which we are 

 illustrating the changes of temperature which take place 

 during a day. The figures of the thermometers and clock 

 faces show the temperatures at different times durin^-the 

 day and the hours. The figure on the squared paper shows 



