638 



PHYSICAL PROPEKTIES OF ICE. 



3. The Composition of Sea- Water and of Salt -Water or 

 Floe-Ice. (Vol. 11. p. 293.) 



In the Appendix are also tables giving the composition of sea- 

 water and of the melted sea- water or floe-ice from different depths 

 of the floe in Wellington Channel, taken during the period at 

 which it became solid for the season. 



The waters contain large quantities of carbonates of lime and 

 magnesia, no doubt due to the presence of those substances in 

 rocks in the neighbourhood. Water taken at spring-tide from a 

 depth of 10 fathoms, contained more chloride of sodium and less 

 sulphate of lime than the water 4 feet below the ice, and contains 

 sulphate of magnesia in place of chloride or bromide of magnesia. 

 The water of the ice is obviously derived from land sources, but 

 the amount of common salt shows that some sea salts are inter- 

 mixed with the natural salts derived from the land. 



Analysis of the Arctic Floe : in 1,000 grains of Water. 





No. 1. ] 



Vo. 3. 



No. 4. 



No. 6. 



Specific gravity - 



1-004 1 



-006 



1-007 



1^007 



Sesquioxide of iron and phosphate - 



•010 



-050 



•010 



•008 



Insoluble lime _ . - 



trace 



009 



•032 



•025 



Soluble lime - . - 



•078 



142 



•113 



•103 



Insoluble magnesia - - - 



•024 



041 



•043 



•052 



Soluble magnesia - - - 



•124 



363 



•471 



•360 



Sodium - - . - 



1-739 1 



933 



2^708 



2-286 



Potassium - - - - 



-594 



096 



•128 



•096 



Chlorine - - - - 



2-723 3 



476 



4-424 



3-950 



Sulphuric acid _ - . 



•372 



472 



-575 



-497 



Carbonic acid - - - 



•052 



128 



•140 



•154 



From Northumberland Sound, lat 76° 52' N., long. 97° W. 

 No. 1. — From the under 6 inches of the floe. 

 No. 3. — From the upper 6 inches of the floe. 

 All collected on October 24, 1852. 



The Composition according to the preceding Table. 





No.L 



No. 3. 



No. 4. 



No. 6. 



Sesquioxide of iron and phosphate - 



•010 



•050 



-010 



•008 



Carbonate of lime - - - 



trace 



•016 



-058 



•046 



Sulphate of lime . - - 



•189 



•344 



-274 



•250 



Carbonate of magnesia 



•050 



•110 



-090 



•110 



Chloride of magnesium 



•289 



-859 



1-122 



•855 



Sulphate of potash - - - 



•133 



•220 



•284 



•220 



Sulphate of soda 



•355 



•300 



•504 



•442 



Chloride of sodium - - - 



4 •132 



4^668 



6^129 



5-454 



Total residue 



5-158 



6-567 



8-471 



7-385 



Kesidue by evaporation 



5-400 



6-600 



8-340 



7^280 



