208 USTDIRECT INJURIES CAUSED BY INSECTS. 



they find their way into houses or warehouses, nothing less 

 hard than metal or glass escapes their ravages. Their fa- 

 vourite food, however, is wood of all kinds, except the teak 

 ( Tectona grandis) and iron-wood (^Sideroxylon), which are the 

 only sorts known that they will not touch ^ ; and so infinite 

 are the multitudes of the assailants, and such is the excellence 

 of their tools, that all the timber-work of a spacious apart- 

 ment is often destroyed by them in a few nights. Exteriorly, 

 however, every thing appears as if untouched; for these 

 wary depredators, and this is what constitutes the greatest 

 singularity of their history, carry on all their operations by 

 sap and mine, destroying first the inside of solid substances, 

 and scarcely ever attacking their outside, until first they have 

 concealed it and their operations with a coat of clay. A 

 general similarity runs through the proceedings of the whole 

 tribe; but the large African species (called by Smeathman 

 Termes hellicosus), T. fatalis, is the most formidable. These 

 insects live in large clay nests, from whence they excavate 

 tunnels all round, often to the extent of several hundred feet ; 

 from these they will descend a considerable depth below the 

 foundation of a house, and rise again though the floors ; or, 

 boring through the posts and supports of the building, enter 

 the roof, and construct there their galleries in various 

 directions. If a post be a convenient path to the roof, or has 

 any weight to support, which how they discover is not easily 

 conjectured, they will fill it with their mortar, leaving only a 

 track-way for themselves ; and thus, as it were, convert it 

 from wood into stone as hard as many kinds of freestone. 

 In this manner they soon destroy houses, and sometimes 

 even whole villages when deserted by their inhabitants, so 

 that in two or three years not a vestige of them will remain. 



These insidious insects are not less expeditious in destroy- 

 ing the wainscoting, shelves, and other fixtures of a house, 



1 It is not its hardness that protects the teak, as the Asiatic Termites attack 

 Lignum Vitae, but probably some essential oil disagreeable to them with which 

 it is impregnated. This is the more likely, since they will eat it when it is old 

 and has been long exposed to the air. Tannin has been conjectured to be the 

 protecting substance, but erroneously, as leather of every kind is devoured by 

 them. (Williamson's East India Fade Mecum, ii. 56.) It is its hardness probably 

 that protects the iron- wood from the African Termites. (Smeathman in Philos. 

 Trans. 1781, 11. 47.) 



