BRIDGMAN. — WATER UNDER PRESSURE. 445 



The I-III Curve ' 473 



The Apparatus for Low Temperatures 474 



The Special Method for Measuring Change of Volume .... 476 



The Conditions under which III Appears 478 



The Data, p, t, Av, AH, AE 481 



The III-L Curve 485 



The Data, p,t,Av,AH,AE 486 



The I-II curve 487 



The Order of Experiment — Proof that II is Distinct from III 487 



Conditions imder which II Appears 489 



The Data, p, t, Av, AH, AE 490 



The II-III Curve 493 



The Special Method for Points on this Curve, both p, t, and Av 493 



The Data, p, t, Av, AH, AE 496 



The III-V Curve 497 



Conditions under which the Curve may be Realized 497 



The data, p, t, Av, AH, AE 499 



The II-V Curve 500 



General Characteristics of the Curve 500 



The Data, p, t, Av, AH, AE 501 



The V-L Curve 502 



Conditions under which V Appears 502 



The Actual Order of Experiment 503 



The Data, p, t, Av, AH, AE 508 



The V-VI Curve 509 



General Characteristics 509 



The Data, p, t, Av, AH, AE 512 



The VI-L Curve 513 



History of the Experiment 513 



The Compressibility Measurements 513 



Electrolytic Conductivity 514 



The Apparatus for the Higher Pressures 516 



The Data p, t, Av, AH, AE 518 



Correction for Av Points at High Pressures 520 



Digression on the Elastic Behavior of the Cylinder under High 



Pressures 521 



The Difference of Compressibility between Solid and Liquid . 523 



The Triple Points 524 



Values of p, t, Av, AH, AE, at these Points 524 



Are the Various Forms really Solid? 526 



Other Possible Forms of Ice 527 



Different Modifications of Ice I 527 



Another Possible Form at High Pressures 528 



Subcooling and Superheating 530 



Superheating with Respect to the Liquid Impossible 530 



Realization of Unstable Forms, Persistent Nuclei in Solid and Liquid 531 



Metastable Limit 532 



Reaction Velocity 533 



Enormous Variation with the Temperature 534 



Compressibility of the Various Forms of Ice 535 



