WATER OF THE IRISH SEA. 293 



by again weighing the filtrate, the amount of the original 

 water employed in the several determinations was easily 

 calculated. The lime in solution was then precipitated as 

 oxalate, with the precaution indicated in the preceding 

 paragraph. 







CaO in 



Water taken. 



CaO obtained. 



1000 grms, 



I. ... 205860 



0*1130 



0*54892 



I. ... 214*020 



o'ii73 



0*54808 



Mean 0*54850 



The total quantity of lime contained in the water of 

 the Irish Channel amounted, according to the determina- 

 tions contained in Section III., to 0'575i2 gram per looo. 

 On subtracting from this the amount contained in lOoo 

 grams of the boiled water existing in combination with 

 sulphuric acid, the quantity of lime remaining amounts to 

 •02662 grm., equivalent to '04754 calcium carbonate per 

 1000 grms. of water. The washed calcium carbonate con- 

 tained a mere trace of magnesium carbonate. This amount 

 of calcium carbonate, although agreeing with the older de- 

 terminations of Bischof and Schweitzer, made on the water 

 of the English Channel, is in all probability too low, on 

 account of the solubility of the carbonate in solution of 

 the alkaline chlorides. No sufficient data exist for sup- 

 plying the proper correction to this result. According to 

 John Davy, only in the vicinity of coasts does sea-water 

 contain calcium carbonate. In the water of the ocean, far 

 away from land, he failed to detect even a trace ; and in 

 the numerous analyses made by Von Bibra on specimens 

 collected in various parts of the world, no mention is made 

 of this ingredient. 



VI. Estimation of the Total Amount of Alkaline Chlorides. 



To the weighed portion of water was added a small 

 quantity of barium chloride, in order to separate the sul- 



