198 HISTORY OF THE 



was at first suspected, and that they are all assi- 

 duously employed in the same pursuits, and that 

 they issue from their respective cells and retire 

 into them at pleasure. Still, however, there are 

 no proofs that those large branches which they 

 inhabit are entirely the construction of such fee- 

 ble and minute animals. But chemistry will be 

 found to lend a clue to extricate us from our 

 doubts in this particular. Like the shells which 

 are formed by snails, muscles, and oysters, these 

 coraline substances effervesce with acids, and may 

 therefore well be supposed to partake of the same 

 animal nature. But Mr Ellis went still farther, 

 and examined their operations just as they were 

 beginning. Observing an oyster-bed which had 

 been for some time neglected, he there perceived 

 the first rudiments of a coraline plantation, and 

 tufts of various kinds shooting from different parts 

 of this favourable soil. It was upon these he tried 

 his principal experiment. He took out the oysters 

 which were thus furnished with coralines, and 

 placed them in a large wooden vessel, covering 

 them with sea water. In about an hour he per- 

 ceived the animals, which before had been con- 

 tracted by handling, and had shewn no signs of 

 life, expanding themselves in every direction, and 

 appearing employed in their own natural manner. 

 Perceiving them therefore in this state, his next 

 aim was to preserve them thus expanded, so as to 

 be permanent objects of curiosity. For this pur- 

 pose he poured, by slow degrees, an equal quan- 

 tity of boiling water into the vessel of sea water 

 in which they were immersed. He then separated 



