VITALITY OF THE MOWANA-TREE. 181 



external injury, not even a fire, can destroy this tree from with- 

 out ; nor can any injury be done from within, as it is quite com- 

 mon to find it hollow ; and I have seen one in which twenty or 

 thirty men could lie down and sleep as in a hut. Nor does cut- 

 ting down exterminate it, for I saw instances in Angola in which 

 it continued to grow in length after it was lying on the ground. 

 Those trees called exogenous grow by means of successive layers 

 on the outside. The inside may be dead, or even removed alto- 

 gether, without affecting the life of the tree. This is the case 

 with most of the trees of our climate. The other class is called 

 endogenous, and increases by layers applied to the inside ; and 

 when the hollow there is full, the growth is stopped — the tree must 

 die. Any injury is felt most severely by the first class on the 

 bark ; by the second on the inside ; while the inside of the exo- 

 genous may be removed, and the outside of the endogenous may 

 be cut, without stopping the growth in the least. The mowana 

 possesses the powers of both. The reason is that each of the 

 lamina? possesses its own independent vitality ; in fact, the baobob 

 is rather a gigantic bulb run up to seed than a tree. Each of 

 eighty-four concentric rings had, in the case mentioned, grown an 

 inch after the tree had been blown over. The roots, which may 

 often be observed extending along the surface of the ground forty 

 or fifty yards from the trunk, also retain their vitality after the 

 tree is laid low ; and the Portuguese now know that the best way 

 to treat them is to let them alone, for they occupy much more 

 room when cut down than when growing. 



The wood is so spongy and soft that an axe can be struck in 

 so far with a good blow that there is great difficulty in pulling it 

 out again. In the dead mowana mentioned the concentric rings 

 were well seen. The average for a foot at three different places 

 was eighty-one and a half of these rings. Each of the lamina? 

 can be seen to be composed of two, three, or four layers of ligne- 

 ous tubes ; but supposing each ring the growth of one year, and 

 the semidiameter of a mowana of one hundred feet in circumfer- 

 ence about seventeen feet, if the central point were in the centre 

 of the tree, then its age would lack some centuries of being as old 

 as the Christian era (1400). Though it possesses amazing vital- 

 ity, it is difficult to believe that this great baby-looking bulb or 

 tree is as old as the Pyramids. 



