260 INSECT ARCHITECTURE. 



terior building supports them on the outside. There 

 are, comparatively speaking, few openings into the great 

 area, and they, for the most part, seem intended only to 

 admit into the nurseries that genial warmth which the 

 dome collects. The interior building, or assemblage of 

 nurseries, chambers, &c., has a flattish top or roof, with- 

 out any perforation, which would keep the apartments 

 below dry, in case through accident the dome should 

 receive any injury, and let in water; and it is never 

 exactly flat and uniform, because the insects are always 

 adding to it by building more chambers and nurseries ; 

 so that the division or columns between the future arched 

 apartment resemble the pinnacles on the fronts of some 

 old buildings, and demand particular notice, as affording 

 one proof that for the most part the insects project their 

 arches, and do not mak^e them by excavation. The area 

 has also a flattish floor, whicli lies over the royal cham- 

 ber, but sometimes a good height above it, having nurse- 

 ries and magazines between. It is likewise waterproof, 

 and contrived to let the water off if it should get in, and 

 run over by some short way into the subterraneous pas- 

 sages, which run under the lowest apartments in the hill 

 in various directions, and are of an astonishing size, 

 being wider than the bore of a great cannon. One that 

 Mr. Smeathman measured was perfectly cylindrical, and 

 thirteen inches in diameter. These subterraneous j)assages, 

 or galleries, are lined very thick with the same kind 

 of clay of which the hill is composed, and ascend the 

 inside of the outward shell in a spiral manner ; and wind- 

 ing round the whole building up to the top, intersect 

 each other at different heights, opening either immedi- 

 ately in the dome in various places, and into the interior 

 building, the new turrets, &c., or communicating with 

 them by other galleries of different diameters, either cir- 

 cular or oval. 



From every part of these large galleries are various 

 sraair covert ways, or galleries leading to different parts 

 of the building. Under ground there are a great many 

 that lead downward by sloping descents, three and four 



