272 = The Vitality.of Toads enclosed in Stone and Wood. 
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FFT: 33 
Arr, VL —Onthe Fitality at Toads enileaila in Stone ata We ods 
. ford. -Communieated by the Author. 
— . senso _ From the Edinburgh New Philosophical Journal. 
Iv the sant of November 1825, I commenced the ‘lions 
periments with a view to explain the frequent discoveries of toads 
enclosed within blocks of stone and wood, in cavities that are ier 
have no communication with the external air. 
~ In one large block of coarse oolitic limestone, (the Osford oolte 
from the quarries of Heddington) twelve circular cells were prepat= 
ed, each about one foot deep and five inches in diameter, and having 
or shoulder at its upper margin fitted to receive a citcular 
of glass, and a circular slate to protect the glass; the margin 
of this double cover was closed round, and rendered impen e 
to-air and water by a luting of soft 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 simi- 
lar plates of glass and slate voleiacgstlade Sits edge by clay. ‘The ob- 
ad of the glass covers was to allow the animals to be inspectet 
without disturbing the clay so as to admit external air or spats! 
the cell. The limestone is so porous that it is easily permeable by 
water; | and | — also by air; the sandstone is very compact. _ 
On the ber 1825, one live toad was placed in 
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 a a 
ve noted by Dr. Daubeny and Mr. Dillwyn, at the time of t 4 
being placed in the cells; that of the smallest was one hundred 5 
sides, and of the lary det one thousand one hundred and ¢ eighty 
five grains. The large and small animals were distributed in equa! 
proportion between the limestone and the sandstone cells. 
These blocks of stone were buried together in my garden : 
three feet of earth, and remained unopened until the 10th of De 
cember 1826, on which day they were examined. Every toa i 
the smaller cells of the compact sandstone was dead, and the bole 
of most of them so much decayed, that they must have been dea 
