Toads enclosed in Wood and Stone. fff 



clay. Twelve smaller cells, each six inches deep and five inches 

 in diameter, were made in another block of compact siliceous 

 sandstone, viz. the Pennant Grit of the Coal formation near 

 Bristol ; these cells also were covered with similar plates of 

 glass and slate cemented at the edge by clay. The object of 

 the glass covers was to allow ihe animals to be inspected, with- 

 out disturbing the clay so as to admit external air or insects in- 

 to the cell. The limestone is so porous that it is easily perme- 

 able by water, and probably also by air ; the sandstone is very 

 compact. 



On the 26th of November 1825, one live toad was placed in 

 each"of the above-mentioned twenty-four cells, and the double 

 cover of glass and slate placed over each of them and cemented 

 down by the luting of clay ; the weight of each toad in grains 

 was ascertained and noted by Dr Daubeny and Mr Dillwyn, at 

 the time of their being placed in the cells; that of the smallest 

 was 115 grains, and of the largest 1185 grains. The large and 

 small animals were distributed in equal proportion between the 

 limestone and the sandstone cells. 



These blocks of stone were buried together in my garden 

 beneath three feet of earth, and remained unopened until the 

 10th of December 1826, on which day they wereexamined. Every 

 toad in the smaller cells of the compact sandstone was dead, and 

 the bodies of most of them so much decayed, that they must 

 have been dead some months. The greater number of those 

 in the larger cells of porous limestone were alive. No. 1, whose 

 weight when immured was 924 grains, now weighed only 698 

 grains. No. 5, whose weight when immured was 1185 grains, 

 now weighed 1265 grains. The glass cover over this cell was 

 slightly cracked, so that minute insects might have entered ; 

 none, however, were discovered in this cell ; but in another cell, 

 whose glass was broken, and the animal within it dead, there 

 was a large assemblage of minute insects, and a similar assem- 

 blage also on the outside of the glass of a third cell. In the 

 cell No. 9, a toad which, when put in, weighed 988 grains, had 

 increased to 1116 grains, and the glass over it was entire ; but 

 as the luting of the cell within which this toad had increased in 

 weight was not particularly examined, it is probable there was 

 some aperture in it, by which small insects found admission. 

 No. 11 had decreased from 936 grains to 652 grains. 



