CHEMICAL CHANGES IN THE COMPOSITION OF SEA- WATER. 



489 



chlorine (halogen), the bases, and the density. For instance, if we take the water repre- 

 sented in the 6th portion of Table IV. we find — 



The chlorine calculated from the density = 19 - 382 



The chlorine calculated from the total bases . . = 19'708 



But the chlorine actually found by analysis . . = 19'891 



all the results being different. 



Let us first take the difference between the chlorine found by analysis, and the chlorine 

 calculated from the total bases found by analysis in the water of Table IV. The analyses 

 of the water (except the first portions drawn off) show less lime than is present in normal 

 sea- water of density 1026 ; this deficiency of lime is evidently due to precipitation of 

 carbonate of lime in the mud. If, however, this deficiency of lime be added to the bases 

 found, and the chlorine then calculated in the usual way, the result will correspond very 

 closely with the chlorine found by analysis, as illustrated in the following table where : 



Column a gives the total bases found in the mud-water on analysis. 



Column b gives the quantity of lime lost by precipitation in the mud (in the first 

 portion there is excess owing to the oxidation of the sulphide of iron before referred to). 



Column c gives this lime in b as sulphate of lime. 



Column d gives a and c added, and the result should give the total bases as sulphates 

 in a normal sea- water. 



Column e gives the chlorine calculated in the ordinary way from column d as a basis. 



Column f gives the chlorine as determined by actual analysis, and column g shows 

 the difference between the chlorine found and that calculated from the bases found, after 

 taking the precipitated lime into consideration, and it will be seen that these differences 

 are very small. 



TABLE B. — Showing that when the Lime precipitated from the Mud- Water (Table IV.) is added on to the 

 Total Bases found, the Chlorine as calculated therefrom practically agrees with that found in the Mud- 

 Water. 



d 

 o 



a. 



Total Bases as 

 Sulphates found 

 in the Mud- 

 Water. 



b. 



Difference of 



Lime from the 



Normal. 



c. 



Column b 



changed into 



Sulphate of 



Lime. 



d. 



a and c added 

 or subtracted 

 (as sign is + 

 or - ), which 

 should give the 

 Total Bases as 

 Sulphates in a 

 Normal Sea- 

 Water. 



e. 



Chlorine calcu- 

 lated from d as 

 for a Normal 

 Sea- Water. 



Chlorine as 



determined by 



Analysis of the 



Mud-Water. 



9- 



Difference be- 

 tween Theory 

 and Analysis. 



1st 

 2nd 

 3rd 

 4th 

 5th 

 6th 



42-195 

 42-399 

 42-430 

 42-396 

 42-378 

 42-564 



+ -0875 

 -•0152 



- -0390 



- -0428 



- -0957 

 -•2101 



+ •212 

 -•037 

 -•095 

 -•104 

 -•232 

 -•510 



41-982 

 42-436 

 42-525 

 42-500 

 42-610 

 43:074 



19-438 

 19-648 

 19-690 

 19-678 

 19-729 

 19-944 



19-391 

 19-666 



19-737 

 19-740 

 19-775 

 19-891 



-•047 

 + •018 

 + •047 

 + •062 

 + •046 

 -•053 



VOL. XXXVII. PART. II. (NO. 23). 



4 E 



