92 



Carbon-Dioxide Content of Sca-Woter at Tortugas. 



Chloride. — The chloride was titrated with t^ilver nitrate, using 

 potassium chromate as indicator, and the density of the water was 

 calculated with the aid of Knudsen's tables. 



a: 



ijj 



-, 0.0S4 



a: 

 ij 

 a. 



to 

 S 



< 

 tr 



o 

 o 



June 10 

 Noon 



12 



13 



14 



15 



16 



17 



18 



.088 



.085 '- 



Cloudy 



N.wind Cloudy Cloudy Rough Fair Fair 



Fig. 1. — Total carbon dioxide and time of day. 



H-ion concentration. — The Ph values were estimated colorimetri- 

 cally by comparison wdth a set of standard tubes very kindly loaned 

 by Professor J. F. McClendon. 



Excess base. — The excess base was obtained by titrating 100 c. c. 

 portions with 0.02 normal sulphuric acid, using methyl red as indi- 

 cator and blowing out the carbon dioxide by means of pure air for 



Table 1. — Determinations on Sea-Water at Loggerhead Key, Tortugas, June 1919. 



[t, temperature, °C.; CI, chlorine, grams per kilogram; D, density; Ph, hydrogen-ion concentra- 

 tion expressed as — log [H + ]; Alk., excess base, in terms of a normal solution, or alkalinity 

 titrated with acid, using methyl red and blowing out CO2; CO2, total, gram per liter.] 



Date, time, and condition of water. 



D 



Ph 



Alk. 



CO2 



1 

 2 

 3 

 4 

 5 

 6 

 7 

 8 

 9 



10 

 11 

 12 

 13 

 14 

 15 

 16 

 17 

 18 

 19 

 20 



21 

 22 

 23 



24 

 25 



June 10, 

 11. 

 11. 

 12, 

 13. 

 13, 

 13, 

 13, 

 14, 



H, 



14, 

 15, 

 15, 

 16, 

 16, 

 16, 

 16, 

 16, 

 17, 

 17, 



17, 

 17, 

 18, 



18, 



18, 



3''30™ p.m.; cloudy. . 

 12 noon; fair 



5''30'°p. m.; cloudy. . 

 12 noon; after rain. . . 



6''45" a.m. ; after rain 



9 50 a.m.; cloudy. . , 

 12 50 p.m.; cloudy. . 



4 10 p.m 



9 45 a.m.; after rain 



and wind 



3h45m p.m.; .^vind 



5 15 p.m.; wind. ... 



6 30 a.m.; wind 



11 a.m 



7''10'" a.m.; fair 



8 15 a.m.; fair , 



11 a.m.; fair 



4''15'° p.m.; fair 



5 45 p.m.; fair 



6 30 a.m 



10 15 a.m.; slightly 



cloudy 



4M5™ p.m.; rainy. . . 



7 p.m.; after rain 



7^15°" a.m.; after 

 shower 



11 a.m.; rain , 



1 p.m.; rain 



1.02373 

 1.02339 

 1.02326 

 1.02332 

 1 . 02258 

 1 . 02342 

 1 . 02352 

 1.02334 



1 . 02344 

 1.02328 



1 . 02333 

 1.02366 

 1.02371 

 1 . 02368 

 1.02359 

 1.02357 

 1.02330 

 1.02330 

 1 . 02354 



1.02361 

 1.02239 

 1.02308 



1 . 02370 

 1.02339 



1 . 02334 



8.23 

 8.19 

 8.19 

 8.21 

 8.20 



8.19 

 8.22 

 8.21 

 8.21 

 8.21 

 8.07 

 8.19 

 8.20 

 8.23 

 8.21 

 8.20 



8.18 

 8.20 

 8.19 



8.18 



0.002370 

 .002368 

 .002398 

 .002394 

 .002394 

 .002410 

 . 002402 



.002406 

 . 002402 

 .002412 

 . 002435 

 . 002424 

 .022368 

 .002414 

 . 002440 

 . 002374 

 .002410 

 .002414 



.002396 

 .002306 

 .002326 



.002418 

 . 002400 

 .002374 



. 0890 

 .0925 



.0902 

 .0924 

 .0913 

 .0900 

 .0897 



.0881 

 .0863 

 .0873 

 .0910 

 .0869 

 .0904 

 .0896 

 .0888 

 .0873 

 .0873 

 .0928 



.0910 

 .0857 

 .0893 



.0918 

 .0928 

 .0879 



