Mr. G. W. Brown on Drift Weed Kelp from Orkney. 209 



" The Potashes of Commerce," m which he gives an analysis of salts of 



wareck — 



Sulphate of potash, ..., 22-2 



Chloride of potassium, 24'6 



Chloride of sodium, 53'2 



This appears to be a general statement of the constitution of the soluble 



salts only. 



Dr. Ure, in his Dictionary of the Arts and Manufactures, published in 



1 840, gives the extremes of his analysis of kelp as follows : — 



/ Sulphate of soda, 8*0 ... 19*0 



o 1 Li 1. ) Carbonate of soda, ...) „ 



Soluble salts < k j ^ ■> . c 3- ^ So ... o-o 



uuiuuic oaii,D-s ^^^ sulphuret of sodium, j 



V Muriates of potash and soda, 36-5 ... 37"5 



Carbonate of lime, 24'0 ... 10-0 



Silica, 80 ... 0-0 



Alumina, with oxide of iron, 9'0 ... 100 



Sulphate of lime, O'O ... 9*5 



Sulphur and loss, 60 ... 8'5 



100 100 



The peculiarity of these resxilts is in the presence of a large quantity 

 of alumina, and the absence of phosphate of lime and alkaline phosphates, 

 which are at variance with the analysis to be described in this paper. 

 The quantity of phosphate of lime in these analysis corresponds with 

 what Dr. Ure terms alumina. It would be difficult to explain the source 

 of such an amount of this earth, as alumina rarely or never enters into 

 the constitution of the vegetable kingdom. 



There are analysis of the ashes of some kinds of fuci, viz., F. digitatus, 

 F. vesiculosus, F. nodosus, and F. serratus, in Liebig's Annalen, vol. 

 liv. p. 350, by M. J. Godechens of Hamburg, published in 1845. The 

 following table gives the calculated mean of these analysis : — 



Potash, 11-67 



Soda, 12-54 



Lime, 11-32 



Magnesia, 8-29 



Oxideofiron, 0*32 



Chloride of sodium, 20*61 



Iodide of sodium, 1-33 



Sulphuric acid 19-77 



Phosphoric acid, 2-19 



Silica, rol 



Carbonic acid, 5-27 



Carbon, 605 



100-37 



