INORGANIC CONSTITUENTS OF PLANTS. 



129 



the same soil, the quantity and quality of the ash varies — the dif- 

 ference being greater the more remote the natural affinities of the 

 plants are. 



The following are the inorganic elements of plants and their 

 combinations : — 



Chlorine (CI.) 

 Iodine (I.) 

 Bromine (Br.) 



Sulphur (S.) 



combined ■with metals forming 

 metals 

 metals 

 metals 



Phosphorus (P.) 

 Potassium (K.) | '" 



Sodium (Na.) 



Calcium (Ca.) 



Magnesium (Mg.) 

 Aluminum (Al.) 

 Silica (Si.) 

 Iron (Fe.) 

 Manganese (Mn.) 

 Copper (Cu.) 



hydrogen 



oxygen 



oxygen 



oxygen 



chlorine 



oxygen 



chlorine 



oxygen 



chlorine 



oxygen 



oxygen 



oxygen 



oxyg«n 

 sulphur 



chlorides, 

 iodides, 

 bromides, 

 sulphides. 



1 sulphuretted hydrogen, or 

 hydro-sulphuric acid, 

 sulphuric acid, 

 phosphoric acid, 

 potash. 



chloride of potassium, 

 soda, 

 chloride of sodium. 



(common salt.) 

 lime, 

 chloride of calcium. 



alumina, 

 silica, 

 oxides 

 and 

 sulphides. 



To these we may add Fluorine (P), the presence of which in plants 

 has been recently noticed. The extraordinary attraction of this 

 element for Silica renders it a matter of impossibility to procure it 

 in a separate state for examination. It is found in those vegetable 

 structures in which Silica abounds, as in the stems of the Graminese 

 and Equisetacese. 



The quantity of inorganic matter or ash. left by plants varies 

 in different species, and in different parts of the same plant. The 

 dried leaves usually contain a large quantity. Saussure found that — 



Dried bark of Oak gave 

 Dried leaves 

 Dried alburnum 

 Dried duramen 



60 parts of ash in 1000 

 53 



i 



2 



The dried leaves of Elm contain more than 11 per cent of inorganic 

 matter, while the wood contains less than 2 per cent ; the leaves of 

 the Willow, 8 per cent, wood, 045 ; leaves of Beech, 6'69, wood, 

 0-36 ; leaves of Pitch-pine, 3-5, wood 0-25. Thus, the decaying 

 leaves of trees restore a large quantity of inorganic matter to the soil. 

 The following tables show the relative proportion of inorganic 

 compounds present in the ash of plants : — 



