Plants. LXXXIF. 



REMARKABLE 



Vol IF. No. 50. 



COMMERCIAL . PLANTS. 



Fio- 1. The Caoutchoii. 



(Hevea g uianenfis.) 



The Caoutchou is the ramarkable tree that 

 provides us with* the elaftiek gum or India- 

 rubber as it is generally called, which in the 

 year 1736 was firft brought to Europe by the 

 famous traveller de la Condamine. It grows 

 in South-Anïerica and. conftitutes a particular 

 genus of plants. Its trunk grows above 60 

 feet high and about three feet in circumfe- 

 rence. Its leaves are threelobed and grow 

 on long ftalks upon the end of the bran- 

 ches, and the little yellowifh flowers Sps 

 pear in cluftres between the -ftalks. The fruit 

 confifts of a large and very hard feed - cafe 

 of three cells (fig. b.) every one of which con- 

 tains two or three grey grains of feed. (fig. c.) 

 When the hark of the trunk is flit , a milk- 

 white, juice comes forth , w hich after its fluid 

 is evaporated in the air, con lenfes into a tough 

 refin and yields the elaftiek gum that at firft 

 view appears to be brown leather, and which, 

 he it ever fo much protracted or extended, 

 immediately contracts again. 



With this gum which at firft is very foft 

 and in coiifequence eafily takes any form,, 

 the Americans cover little earthen flafks,. and 

 after having dried the covering at the fire, 



they break the earthen mould within , and 

 fhake the pieces out of the neck of the flafk; 

 hence we generally receive the elaftiek gum 

 in the form of little flafks. 



Fig. 2. The Egyptian Mini of a. 



[Mimo fa nilotica.) 



The Egyptian Mimofa or Acacia is 

 the tree that f applies us with the well 

 known Arabian Gum. It grows wild in the 

 arid parts of Arabia, Egypt and Africa. The 

 tree attains a confi der ab le height; its tender 

 pennated leaves are formed like thofe of the 

 Äcacia (Fig. a.); its flowers are yellow and 

 round like a ball (fig. b) , and the long, brown, 

 and indented hufk contains the oval feeds or 

 beans. 



The Arabian Gum iffu.es here and there 

 from the bark and forms itfelf on the outfide 

 cruft into pieces of the fize of a Walnut, like 

 the gum on our cherry-trees. , Its colour 

 is white , yellow , or brown ; it diffolves 

 very eafily in Water and comes from the Le- 

 vant to Europe. It is ufed in Medicine as 

 well as in painting and fi Ik - manufactures , 

 and conftitutes therefore a very ufeful com- 

 mercial article. 



