192 OF INSECTS. 



to the other of this line ; nor muscles to enable it to spring 

 or dart to so great a distance. Yet its Creator hath laid 

 for it a path in the atmosphere ; and after this manner. 

 Though the animal itself be heavier than the air, the thread 

 which it spins from its bowels is specifically lighter. This 

 is its balloon. The spider left to itself would drop to the 

 ground ; but being tied to its thread, both are supported. We 

 have here a very peculiar provision ; and to a contempla- 

 tive eye it is a gratifying spectacle, to see this insect wafted 

 on her thread, sustained by a levity not her own, and trav- 

 ersing regions, which, if we examined only the body of 

 the animal, might seem to have been forbidden to its na- 

 ture. 



I must now crave the reader's permission to introduce 

 into this place, for want of a better, an observation or two 

 upon the tribe of animals, whether belonging to land or 

 water, which are covered by shells. 



I. The 5//6'Z/5 of s??«?75 are a wonderful, a mechanical, 

 and, if one might so speak concerning the works of nature, 

 an original contrivance. Other animals have their proper 

 retreats, their hybernacula also or winter quarters, but the 

 snail carries these about with him. He travels with his 

 tent; and this tent, though as was necessary, both light 

 and thin, is completely impervious either to moisture or air. 

 The young snail comes out of its egg with the shell upon 

 its back ; and the gradual enlargement which the shell 

 receives, is derived from the slime excreted by the animal's 

 skin. Now the aptness of this excretion to the purpose, its 

 property of hardening into a shell, and the action, w^iatever 

 it be, of the animal, whereby it avails itself of its gift, and 

 of the constitution of its glands, (to say nothing of the work 

 being commenced before the animal is born,) are things, 

 which can, with no probability, be referred to any other 

 cause than to express design ; and that not on the part of 

 the animal alone, in which design, though it might build 

 the house, could not have supplied the material. The will 

 of the animal could not determine the quality of the ex- 

 cretion. Add to which, that the shell of a snail, with its 

 pillar and convolution, is a very artificial fabric ; whilst a 

 snail, as it should seem, is the most numb and unprovided 

 of all artificers. In the midst of variety, there is likewise 

 a regularity, which would hardly be expected. In the 

 same species of snail the number of turns is, usually, if 

 not always, the same. The sealing up of the mouth of 



