256 
Proceedings of the Royal Society 
that the ‘‘computed” distances were derived from the straightdine 
measurements of statute miles from a map, thus omitting the length 
of windings of the roads. But this explanation also is quite in- 
sufficient, as, in the first place, the windings will not account for 
even as much as half of the difference of numbers of computed or 
reputed and statute miles ; secondly, the difference between com- 
puted and statute miles exists just as plainly on the straight Roman 
roads, where no windings exist, as on the winding roads ; and finally, 
as we shall see, these computed miles are the same as those in use in 
the thirteenth century, when maps were very scarce, and it is quite 
unlikely that the populace should have adopted their current 
reckoning of every-day journeys from the measurements of a few 
distorted monastic manuscripts. Hence, De Morgan’s explanation 
is certainly insufficient; and in the latter part of his article he 
argues for an old mile equal to 1 J statute miles, concluding thus : 
“We think it by no means improbable that 100 ancient miles are as 
much as 150 statute miles, and tolerably certain that they exceeded 
145 such miles.” Thus he agrees with Sir Henry Ellis, who writes, 
“ the ordinary mile of England was nearly a mile and a half 
of the present standard.”'^ 
A point on which De Morgan lays much stress is the shortening of 
the roads in modern times, and the much greater length he supposes 
them to have formerly been. The only evidence adduced is a com- 
parison of four of the distances by Ogilby (1675) in statute miles 
with modern statements of the same, which may not have followed 
exactly the same route. But on measuring the modern distances f 
of about ninety of Ogilby’s statements, there does not appear to be 
any constant difference between his reckoning and the present roads; 
and in single lengths Ogilby was certainly in error occasionally, since 
he sometimes gives a less distance than the shortest practicable line. | 
Eroni a general consideration of the history of roads, and the 
* Introduction to Domesday Book (1833), i. 145 et seq. 
4 Tlie actual distances in statute miles are here ascertained from the county 
maps of The National Gazeteer (1865 ?); these are very clear, and appear to be 
accurate on comparison with the Ordnance Survey. The windings of the roads 
are in all cases carefully attended to in the measurement. 
%E.g., High Wycombe to Tetsworth, 12’0 Ogilby, =:13'6 miles really; 
Frestein to lihyadergowy, 127 Ogilby, =14 ‘4, or more, really; Eoyston to 
Huntingdon, 19 '2 Ogilby, =21 ’4, or more, really. 
