SEA H AM !!()() AS A SOTKCK OF POTASH. IO7 



The composition of the water-sokible portion is given in Table IIL 



Table No. III. "'< 



Composition uk Water- Soluble Portion, Calculated in Terms ok Whole Ash. 



Locality Sea Point. Clifton-on-Sea. Sea Point. Camps Bay. Average. 



Stem. Leaves. Stem. Leaves. Stem. Leaves. Stem. Leaves. Stem. Leaves- 

 Lime 60 .26 .35 '.32 .53 .16 .61 .40 .52 .29 



Magnesia 79 .13 .16 .16 .29 .16 .43 .28 .42 .18 



Potash as K2O ... .37.45 25.38 39.63 25.32 36.58 25.62 39.98 25.44 38.41 25.44 

 Soda (calculated) as 



XazO TI.14 20.99 11.64 -'O.60 12.17 21.21 II. 01 19.96 It. 49 20.69 



Carbon dioxide ... 3.29 2.12 2.7J 1.87 2.70 1.16 3.16 2.60 2.98 1.94 



Sulphuric oxide ... 3.61 7.92 4.45 8.29 4.58 8.55 4.44 9.04 4-27 8.45 



?'?'''"^ 3469 33.30 35.58 33.02 34.32 34.67 35.30 30.85 34-97 32.96 



Ratio — 



Potash; Soda ... 3.36 r.21 3.40 r.24 3.00 1.21 3.63 1.27 3-35 '23 



It will be seen that there are not ver}' great variations in 

 composition, and the conclusion to be drawn would appear to 

 be that the sea bamboo is fairly constant in composition. At 

 this point of the investigation, however, I was fortunate enough 

 to be able to visit Kommetje, a spot where the sea bamboo grows 

 more thickly than at any other place in the Cape Peninsula. 

 There was a heavy sea running at the time, and as the seaweed 

 was growing some distance away from the shore, it was out of 

 the question to take a sample from a growing plant. The beach 

 was, however, strewn in every direction, as far as one could 

 see, with immense quantities of this particular kind of seaweed, 

 and I decided to take what was at my disposal. I selected the 

 largest specimen of a plant evidently freshly washed up, and 

 cut a section from the stem, and took i^art of the leaves. Some 

 idea of the size may be gathered from the statement that the 

 stem was about 12 feet long, and at the thickest part measured 

 120 millimetres in diameter, while the walls of the stem were 

 15 mm. thick. There was no means of taking the whole plant, 

 so that no ratio between stem and leaves is given, nor are the 

 figures for the percentage of moisture and of ash considered 

 sufificiently reliable to be included. The composition of the ash 

 was as follows : — 



In Percentages 



Stems. Leaves. 



Total soluble salts 92.08 78.69 



Lime 3.10 8.30 



Magnesia 2.08 5.78 



Phosphoric oxide .47 2.66 



