LIQUIDS AND ALLIED EXPERIMENTS. 



63 



a length of but 4.5 to 5.5 cm. and the experiment continued under these 

 conditions. The records are given in tables 18, 19, 20, and figs. 19 a, b, c, 

 the long swimmers showing astonishingly slow diffusion. Both were moved 

 to the vault of constant temperature on October 25. (Cf. c in fig. 19B). 



Table 18. — Air-air through water. Vessel £ (single tube). il/= 14.8968 grams; C= 53. 51 ; 

 p a = 2.^66; float, 2r=3.oo cm.; vessel, 2r=4.j cm. 



Date. 



Barom- 

 eter. 



t 



* 



Vo 



Date. 



1 Barom- 

 eter. 



/ 



// 



t'o 



Sept. 30 



. 76.90 





 17-4 



67.85 



7-459 



Oct. 10 



• 76-27 



O 



22.8 



68.51 



7.408 



Oct. 1 



. 76.03 



18.0 



67.36 



7 



391 



1 1 



■ 76.72 



21.7 



68.31 



7.410 



2 



. 76.58 



18.2 



67.35 



7 



385 



12 



. 76.40 



22.7 



68.61 



7.420 



3 



■ 76.33 



20.4 



67.86 



7 



39 1 



'4 



. 76.88 



22.5 



68.50 



7-413 



4 



76.10 



22.8 



68.74 



7 



433 



'5 



. 76.08 



22.4 



68.33 



7-397 



5 



76.69 



20.4 



68.39 



7 



449 



16 



. 76.92 



19.7 



67.23 



7.338 



7 



. 75-68 



19.0 



67- 53 



7 



387 



'7 



■ 76.44 



20.5 



67.03 



7.299 



8 



• 76.34 



19.6 



67.51 



7 



37' 



18 



. 76.38 



22.2 



67.49 



7.310 



9 



. 76.78 



21 .2 



67.89 



7-376 



'9 



• 75-97 



22. 1 



67.49 



7.312 



Table 19. — Air-air through water. Vessel F (single tube). i/=23.5450grams; £=84. 58; 

 p,7 = 2.466; float, 2r = 3.oocm.; vessel, 2r=4-7 cm. 



Date. 



Barom- 

 eter. 



t 



H 



»o 



Date. 



Barom- 

 eter. 



' 



H \ 



Vo 



Sept. 30. . 



76.90 



° 

 17-4 



65.77 1 •• 



4 28| 



Oct. 21 . . 



77.29 





 21 .2 



| 65.64 11 



271 



Oct. 1 . . 



76.03 



18.0 



65.40 1 1 1 



342! 



22. . 



77.08 



21 .2 



| 65.47 11 



242 



2. . 



76.58 



18.5 



65.45 1 11 



333, 



23.. 



76.05 



22.3 



; 65.86 11 



273 



3- • 



76.33 



20.4 



65.97 11 



3571 



24. . 



75-29 



235 



: 66 . 29 11 



304 



4-- 



76. 10 



22.8 



66.77 I' 



410 



25. . 



75.68 



20.3 



65.61 11 



2QQ 



5-- 



76.69 



20.4 



66.26 11 



407 



26.. 



75.66 



20.2 



65.41 11 



266 



7-- 



75.68 



19.0 



65.67 n 



354 j 



28.. 



76.20 



20.2 



,65.13 11 



218 



8.. 



76.34 



19.6 



65 . 70 11 



338 



29.. 



76.58 



20.0 



65.09 11 



219 



9. . 



76.78 



21 .2 



66.12 11 



353 



30. . 



75.80 



19.9 



65.06 11 



217 



10. . 



76.32 



22.8 



66.52 11 



368 



Nov. 1 . . 



75-9' 



19.5 



64.91 11 



205 



11.. 



7672 



21.7 



66.37 II 



379 



2. . 



75.62 



19-5 



64.76 11 



I79 



12. . 



76.40 



22.7 



66 . 60 11 



384 



4- • 



77-33 



18.9 



64.45 11 



147 



14. . 



76.88 



22.5 



66.51 11 



376 



5- • 



76.89 



18.5 



64.36 11 



'44 



15.. 



76.08 



22.4 



66.39 n 



359 ' 



6.. 



76.82 



18.3 



64.27 11 



136 



16.. 



76.92 



19.7 



65.54 11 



306; 



!■■ 



76.02 



.8.3 



64.16 11 



II 7 



17.. 



76.44 



20. 5 



65.53 11 



277: 



8.. 



75.07 



18.7 



64.26 11 



no | 



18.. 



76.38 



22.2 



66 . 04 11 



305 j 



9. . 



75-55 



18.9 



64.32 1 11 



124 



19.. 



75-97 



22. 1 



66 . 04 11 



309 



11.. 



76.33 



18.9 



64.25 | 11 



I !2 



The identity of the two curves, figs. 19 a and B,in their indirect fluctuation 

 with temperature is noteworthy, showing that the relative results obtained 

 with a given apparatus are quite trustworthy. The new feature which the 

 curves bring out, however, is unexpected. In other words, the rate of 

 diffusion, which was incidentally found to be relatively large in table 16, 

 is here relatively small, only about one-tenth of the former value. If the 

 mean slope of the curve, fig. 19 a, be taken, the data for the diffusion con- 

 stants are 



t' = 0.0042 c.c./day or io 10 /c = 0.374 

 where the curve of fig. 19 b for the same interval of time would have given 

 an identical result. It was therefore to be feared, in so far as these results 



