Relation to Pressun and Temperature. 47 ( .» 



and Massieu, 1 but that important experimental evidence is 

 given in favor of rhe probable truth of the principle bv Ram- 

 and Young. Bee below. AmagatV work on the compres- 

 sion of gases mnst be mentioned because of its important 

 bearing OD pressure measurement. In two critical researches 

 Mees" perfects Regnanlt'e piezometer and re-determines the 

 compressibility of water. Tait 1 and his pupils, Buchanan 6 , 

 Marshal, Smith and Omond, 6 and others carry the inquiry into 

 compressibility and maximum density of water into much de- 

 tail, and the data are theoretically discussed by Tait. Pres- 

 sures as high as 600 atm. are applied. Solutions and alcohol 

 are also tested for compressibility. Pagliani, 7 Palazzo and 

 Vicentini, 8 using Regnault's piezometer, publish results for 

 water and a number of other substances, mostly organic. 

 They also examined mixtures. Temperature is varied between 

 0° and 100°. The results are discussed at length and show 

 the insufficiency of Dupre's formula. DeHeen 9 who has 

 spent much time in studying the volume changes of liquid, 

 deduces a formula of his own chiefly in reference to the ther- 

 mal changes of compressibility. Theory is tested by experi- 

 ments, the researches which Amagat, 10 published at about 

 this time are remarkable for the enormous interval of hydro- 

 static pressure (3000 atm.) applied. Ether and water are oper- 

 ated on. In later work these 11 researches are extended to include 

 other liquid substances with the ulterior object of locating the 

 lower critical temperature. The behavior of water is fully 

 considered. Grimaldi" critically discusses the earlier work on 

 the maximum density of water. He also examines the volume 

 changes produced in a number of organic substances 13 by tem- 

 perature (0° to 100°) and pressure (0 to 25 atm.), and finds 

 Dupre's, DeHeen's and Konowalow's 14 formulae insufficient. 



1 Massieu: C. R., Ixxxvii, p. 731, 1878. 



2 Amagat: C. R., lxxxix, p. 437, 1879; ibid , xc, pp. 863, 995, 1880; ibid., xci, 

 p. 428, 1880. and elsewhere. 



; Mees: Beiblatter, iv, p. 512, 1880; viii, p. 435, 1884. 



4 Tait: Nature, xxiii, p. 595, 1881 ; Challenger Reports, ii, 1882, app., pp. 1 to 

 40; Proc. Roy. Soc. Ed., xi, p. 813. 1882-83 ; ibid., xii, 1883-84, pp. 45, 223, 226, 

 757 ; ibid., xiii, p. 2, 1884-85. 



5 Buchanan: Proc. Roy. Soc. Ed., x, 1880, p. 697. 



6 Marshal, Smith and Omond: Proc. Roy. Soc. Ed., xi, pp. 626, 809, 1882-83. 



7 Pagliani and Palazzo: Beibl., viii, p. 795, 1884; ix. pp. 149, 626, 809, 1885. 



8 Pagliani and Vicentini: Beibl , viii, p. 794, 1884; Journ. de phys.. (2) xxx, p. 

 461, 1883. 



9 DeHeen: Bull. Soc. Roy. Belg., (3), ix, 1885, p. 550; Journal de phys., (2), 

 viii, p. 197. 1889. 



10 Amagat: C.R., ciii, p. 429, 1886. 



11 Amagat: C. R., civ, p. 1159, 18S7; ibid., cv, pp. 165, 1120, 1887. 

 u Grimaldi: Beiblatter, x, p. 338, 1886. 



13 Grimaldi: Beiblatter, xi, pp. 136, 137, 138,1887; Ztschr. fur phys. chem., 

 ii, p. 374, 1888. 



16 Konowalow: Ztschr. fur phys. chem., ii, p. 1, 1888. 



