488 



Messrs. Carpenter, Jeffreys, and Thomson [Nov. 18, 



II. — Results of the Analysis of Eight Samples of Sea-Water collected 

 during the Third Cruise of the 'Porcupine.' By Dr. Frankland, F.R.S. 



Royal College of Chemistry. 

 November 15th, 1869. " 



Dear Dr. Carpenter, — Herewith I enclose results of analyses of 

 the samples of sea-water collected during your recent cruise in the f Por- 

 cupine.' 



I shall not attempt to draw any general conclusions from these results ; 

 your own intimate knowledge of the circumstances under which the differ- 

 ent samples were collected will enable you to do this much better than I. 



There is, however, one point which is highly remarkable and to which I 

 would draw your attention ; it is the large amount of very highly nitroge- 

 nized Organic matter contained in most of the samples, as shown by the 

 determinations of organic Carbon and organic Nitrogen, and the proportion 

 of organic Carbon to organic Nitrogen. For the purposes of comparison, I 

 have appended the results of analyses of Thames-water and of the water 

 of Loch Katrine, the former representing probably about a fair average 

 of the proportion of organic nitrogen reaching the sea in the rivers of 

 this country, but being presumably considerably greater than that con- 

 tributed by rivers in other parts of the world. If this be so, it follows 

 either that soluble nitrogenous organic matter is being generated from 

 inorganic materials in the sea, or that this matter is undergoing con- 

 centration by the evaporation of the ocean, — the rivers and streams con- 

 tinually furnishing additional quantities whilst the water evaporated takes 

 none away. 



The amounts of Carbonate of Lime given in the Table are obtained by 

 adding the number 3 (representing the solubility of carbonate of lime in 

 pure water) to the temporary hardness which denotes the carbonate of lime 

 thrown down on boiling. As the determination of temporary hardness in 

 water containing so much saline matter is not very accurate, the numbers 

 in the columns headed " temporary hardness'' and " carbonate of lime " 

 must only be regarded as rough approximations to the truth ; moreover, 

 a small proportion of carbonate of magnesia is mixed with the carbonate 

 of lime and estimated with it. 



In all their peculiar features these analytical results agree with those 

 which I have previously obtained from numerous samples of sea-water 

 collected by myself off Worthing and Hastings. 



Yours very truly, 



E. Frankland. 



