. r >64 ] 
pojition, the \ wind moves 4 miles an hour ; and for 
every 6 turns in a minute , <?/" the e?ilarged fails in 
their beft pofition , the wind will move 5 <37; 
hour. 
The following table, which was communicated 
to me by my friend Mr. Roufe, and which appears to 
have been conftrudted with great care, from a con- 
fiderable number of fadts and experiments, and which 
having relation to the fubjedt of this article ; I here 
infert it as he fent it to me : but at the fame time mud; 
obferve, that the evidence for thofe numbers wdiere 
the velocity of the wind exxeeds 50 miles an hour, 
do not feem of equal authority with thofe of 50 miles 
an hour and under. It is alfo to be obferved, that 
the numbers in col. 3. are calculated according to the 
fquare of the velocity of the wind, which, in mode- 
rate velocities, from what has been before obferved, 
will hold very nearly. 
\ 
Ta b le 
