APPENDIX. 359 
bleak Sci'eatn of (harp Air, than to (land in 
the fame open Air under the Shelter of a 
Hedge or Wall ; and as the Hand put into 
cold Water, will be fenfible of a greater De- 
gree of Cold, if the Hand be moved to and 
fro in the Water, than if it be held ilill ; bc- 
caufe in both thefe Cafes, the ftagnanc Flu- 
ids which immediately touch the Body, ac-' 
quire by a conftant Touch a Degree of 
Warmth, more nearly approaching to that 
of the Body ; whereas when there is a con- 
tinued Succeflion of cold Fluid ftriking on 
the Body, it muft needs then be afteded 
with a greater Degree of Cold. And the 
Difference is the fame between a River and 
a Pond, the Ground at the Bottom of the 
River being reduced to a much colder State, 
by the continual flow of Water over it, than 
the Bottom of a Pond whofe Water is flae- 
nant'. And in Confirmation of this, it is 
obferved, that it freezes firfl: at the Bottoms, 
where the Stream is gentle, but not at all ac 
the Bottom of deep Holes, whofe Depth 
ftielters them from the continued Courfe of 
the Stream : For which Reafbn the Fiflics 
are obferved to retreat into the deeper Places 
in very cold Weather. 
A a 4 And 
