xxaviii CONTENTS. 



BOOK HI. 



METHODS OF MEASUREMENT. 

 CHAPTEB XIII. 



THE EXACT MEASUREMENT OF PHENOMKNA. 

 9KCTION I 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 



10. Measurements by Natural Coincidence 292 



11. Modes of Indirect Measuiei^eai 296 



12. Comparative Use of Measuring Instruments 299 



13. Systematic Performance of Measurements 300 



14. The Pendulum 302 



15. Attainable Accuracy of Measurement . 303 



CHAFPER XIV. 



UNITS AND STANDARDS OF MEASURF-MEE 1 ! 



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 ; . ~i . .314 



5. The Pendulum Standard i . .315 



6. Unit of Density 316 



7. Unit of Mass 317 



8. Natural System of Standards 318 



9. Subsidiary Units 320 



10. Derived Units 321 



11. Provisional Units 323 



12. Theory of Dimensions . 825 



13. Natural Constants 328 



14. M athematical Constants . ... 330 



15. Physical Constants 331 



16. Astronomical Constants . 382 



17. Terrestrial Numbers . . - . . . 833 



18. Organic Numbers :i33 



19 Social Numbers . . . 384 



