188 NATURAL HISTORY OF SELBORNE. 
accident, to which they were continually liable, our provident 
forefathers always kept^a shrew-ash at hand, which, when once 
medicated, would maintain its virtue for ever. A shrew-ash was 
made thus :* — Into the body of the tree a deep hole was bored 
with an auger, and a poor devoted shrew-mouse was thrust in 
alive, and plugged in, no doubt, with several quaint incantations 
long since forgotten. As the ceremonies necessary for such a 
consecration are no longer understood, all succession is at an 
end, and no such tree is known to subsist in the manor, or 
hundred. 
As to that on the Plestor 
The late vicar stubb'd and burnt it," 
when he was way-warden, regardless of the remonstrances of the 
by-standers, who interceded in vain for its preservation, urging 
its power and efficacy, and alleging that it had been 
Religione patrum multos servata per annos.'* 
I am, &C. 
LETTER XXIX. To the Hon. DAINES BARRINGTON. 
DEAR SIR, Selhorne, Feb, 7, 1776. 
In heavy fogs, on elevated situations especially, trees are perfect 
alembics : and no one that has not attended to such matters can 
imagine how much water one tree will distil in a night's time, 
by condensing the vapour, which trickles down the twigs and 
boughs, so as to make the ground below quite in a float. In 
Newton-lane, in October 1775, on a misty day, a particular oak 
in leaf dropped so fast that the cart-way stood in puddles and 
the ruts ran with water, though the ground in general was 
dusty. • 
In some of our smaller islands in the West-Indies, if I mistake 
not, there are no springs or rivers ; but the people are supplied 
with that necessary element, water, merely by the dripping oi 
some large tall trees, which, standing in the bosom of a moun- 
tain, keep their heads constantly enveloped with fogs and clouds, 
from which they dispense their kindly never-ceasing moisture ; 
and so render those districts habitable by condensation alone. 
Trees in leaf have such a vast proportion more of surface than 
* For a similar practice, see Plot's Staffordshire. \ 
