xxxriii CONTENTS. 



BOOK m. 



METHODS OF MEASUREMENT. 

 CHAPTER X1I1. 



THE EXACT MEASUREMENT OF PHENOMENA. 

 SECTION * AGE 



1. The Exact Measurement of Phenomena . . . .270 



2. Division of the Subject 274 



3. Continuous quantity .... . 274 



4. The Fallacious Indications of the Senses .276 



5. Complexity of Quantitative Questions . 278 



6. The Methods of Accurate Measurement .... .282 



7. Conditions of Accurate Measurement . 282 



8. Measuring Instruments .... 284 



9. The Method of Repetition 288 



1 0. Measurements by Natural Coincidence 292 



11. Modes of Indirect Measuierteai 296 



12. Comparative Use of Measuring Instruments 299 



13. Systematic Performance of Measurements 300 



14. The Pendulum 302 



15. Attainable Accuracy of Measurement . 303 



CHAPTER XIV. 



UNITS AND STANDARDS OF MEASUllKMEX'I 



1. Units and Standards of Measurement 305 



2. Standard Unit of Time 307 



8. The Unit of Space and the Bar Standard 312 



4. The Terrestrial Standard 314 



5. The Pendulum Standard 315 



6. Unit of Density .316 



7. Unit of Mass 317 



8. Natural System of Standards 319 



9. Subsidiary Units 320 



10. Derived Units 321 



11. Provisional Units 323 



12. Theory of Dimensions . . 325 



13. Natural Constants 328 



14. Mathematical Constants ; . . . . 330 



15. Physical Constants ... . 331 



16. Astronomical Constants . 332 



If. Terrestrial Numbers ...... 333 



18. Organic Numbers ... .338 



19 Social Numbers . . 884 



