scale

Ogilby's Hampshire 1675
Scale Ogilby's maps have no scale line. The declared scale of all the maps is 1 inch to 1 statute mile, 1 to 63360. Comparing the routes with the today's maps, judging as best one may what the route is now, the scale seems to be close to this figure.

The scale may be estimated by measuring the length of the marked miles. From this procedure (measurements are given below) the map scale is about:-

1 to 63800 or 1 mile to 1 inch

3. The Scale by which the said Road is Protracted, is according to one Inch to a Mile, or the 63'360th. Part of a Mile; ...
Note that the statute mile is used, which at that time was not as established as it is now.
II. In Dimensuration, We might here Treat of the Several Measures ... as to the English Mile it is deduc'd from a Barley-Corn, whereof 3 in length make an Inch, 12 Inches a Foot, 3 Feet a Yard, 3 Feet 9 Inches an Ell, 5 Feet a Pace, 6 Feet a Fathom, 5 Yards and an half or 16 Feet and an half a Pole, Perch or Rod, 40 such Poles a Furlong, and 8 Furlongs a Mile; so that a Mile English contains 8 Furlongs, 320 Poles, 1'056 Paces, 1760 Yards, 5'280 Feet, and 63'360 Inches.

Notes about surveying and measures.


Mile measurements 

A sample of 1 mile intervals were measured on several sheets of 
the map.  Care was taken to measure pretty straight road segments, 
and to measure 8 furlongs - ignoring mistaken numberings.  The range 
of lengths of segments is small, but they are not all exactly 
25.4mm!  The overall average length of a mile segment is:-

     25.22 +- 0.01 mm

The map scale is:-

     1 to 63800
     1.01 miles to 1 inch

The measurements were:-

     pl.25     pl.30     pl.32     pl.97

     25.3      22.9      25.4      26.0
     23.8      23.8      25.7      25.3
     23.1      22.9      24.3      24.9
     24.6      23.3      24.8      25.2
     24.0      23.2      25.2      25.4
     24.2      25.0      25.2      25.2
     23.8      25.0      24.8      25.3
     25.9      24.9      25.5      25.6
     26.1      24.8      24.4      25.8
     26.3      26.8      25.0      26.2
     25.7      27.1      23.9      25.2
     26.8      26.5      26.9      25.5
     25.4      25.4      25.7      25.7
     25.5      24.2      26.0      25.6
     25.2      24.9      25.7      25.6
     25.6      23.6      25.9      25.6
     26.3      25.4      25.9      26.0
     26.1      25.4      25.9      25.8
     25.2      23.8      23.9      25.8
     25.6      24.3      23.2      24.7
     26.3      24.5      25.7      25.3
     26.0      24.8      24.7      25.2
               24.6      24.8      24.9
                         25.3      25.8
                         24.9
                         26.0
                         25.2
                         25.6
                         26.6
                         24.6
                         28.5
                         25.9
                         25.8

    556.8     567.1     836.9     611.6
     22        23        33        24

total 2572.4 for 102 readings, average 25.220

Error in a reading 0.2mm in 25.4, ie 1%; error in average 0.1%

Ogilby's Hampshire 1675, contents
feature list
General index
Old Hampshire Mapped