fi8 TRANSITION OF INORGANIC INTO ORGANIC MATTER. 



buried in the ground, contained no sugar, but a substance possessing 

 the principal characters of gum.* It was probably an effect of the 

 season ; for Knight states, that he never could discover the least 

 trace of saccharine matter during winter in the alburnum either of 

 the stem or of the roots of the sycamore. f 



SAP OF THE BAMBUSA GUADUAS. 



The guaduas grows in the hot and marshy countries of the tropi- 

 cal regions ; this grass frequently attains the enormous height of 

 from 65 to 100 feet. Its stem, which is hollow, is divided through 

 its entire length into joints spaced rather regularly at distances of 

 from 11 to 12 inches. Each joint indicates the presence of a woody 

 partition, which seems to divide the stem of the guaduas into so 

 many super-imposed tubes. On perforating it immediately above a 

 knot, a clear limpid fluid flows out, which cannot be distinguished 

 from the purest water. This indeed is a store of water of which 

 travellers have frequcMilly availed themselves. Tliis sap, as 1 have 

 been assured by the iidiabitants of the countries where I observed 

 the guaduas, never completely fdls the hollow space in<'luded be- 

 tween two joints. Analysis satisfied me that the sap of the guaduas 

 is almost pure water. Re-agents detected merely traces of sulphates 

 and chlorides. On evai)oratin«T a considerable quantity of it, I wa« 

 able to discover, independently of these traces of soluble salts, a 

 very small proportion of organic matter and of silica ; the latter sub- 

 stance is probably the element which predominates in the sap of the 

 guaduas. 



SAP OF THE BANANA PLANT, (mLSA PARADISICA.) 



The sap of the banana possesses a well-marked astringent taste ; 

 It reddens tincture of litmus. Immediately after psc:i{)ing from the 

 plant, it is limpid and colorh^ss, like water ; nevertheless, it possesses 

 the property of imparting a yellow color to stutTs immersed in it. 

 Exposed to the air it becomes turbid, and throws down flocculi of a 

 dirty rose color. It is to the action of oxyizen that this deposite is 

 owing; for it takes place only in contact with the air. After the 

 formation of this deposite, the sap no longer colors stulfs immersed 

 in it. From a chemical examination which I instituted of the sap 

 of the banana, during my sojourn on the banks of the Magdalena, I 

 think I mav stale that it contains gallic acid, acetic acid, chloride 

 of sodium, salts of lime and potash, and silica. 



The sap of vegetables, elaborated during its passage through the 

 leaves, acquires adililional consistence. It generally c«intains pecu- 

 liar principles, which are the result of this elaboration, and these 

 now constitute the liquid which is usually designated by the name of 

 the particular juice of the plant from which it is procured. This 



• Annfiles dii Miis^mn (t'Histoirc NaturcUo. t. ii. 



* Knight, quoted In Annates do TAKriculture Fran^aise, t. v. 2e siric, p. 3» 



