National Grid References

Speed's Hampshire 1611
NGRs Simple mathematics was used to crudely superimpose the national grid on Speed's map. The difference between the map projections used by the NGR system and used John Speed has been ignored. 'Centres' of the the old and the Ordnance Survey maps of the county were superimposed at an average position of twenty or so prominent towns; the orientations and scales were matched by averaging the directions and distances of these places from the centres on each map; it is then possible to draw the NGR from the modern map upon the image of the old. The calculations were done by a computer using a program written by MN, OLDMAPS.exe; fuller notes about the process are provided in the software notes, OLDMAPS.rul.

File SPEED1.pts has readings of positions of recognisable places on the old map, using (x,y) coordinates on the old map.
Points
file		 

file: SPEED1.pts

reference points for map SPEED1
to work in OLDHANTS.exe

@pl Alton @ngr SU717396 @xy (33.20,26.50)
@pl Andover @ngr SU365458 @xy (18.69,25.79)
@pl Basingstoke @ngr SU634527 @xy (29.56,30.51)
@pl Bradley @ngr SU635418 @xy (32.61,27.20)
@pl Burghclere @ngr SU469610 @xy (22.08,32.19)
@pl Buriton @ngr SU740200 @xy (33.89,17.77)
@pl Christchurch @ngr SZ159925 @xy (12.10,2.31)
@pl Fareham @ngr SU575061 @xy (29.02,11.29)
@pl Fordingbridge @ngr SU150145 @xy (12.16,11.58)
@pl Grately @ngr SU275420 @xy (13.92,23.01)
@pl Havant @ngr SU717062 @xy (34.29,11.05)
@pl Hawkley @ngr SU746291 @xy (34.51,22.28)
@pl Kingsclere @ngr SU525586 @xy (24.71,32.46)
@pl Lymington @ngr SZ322954 @xy (18.88,5.27)
@pl Nether Wallop @ngr SU304364 @xy (15.09,21.37)
@pl Odiham @ngr SU740509 @xy (33.29,30.60)
@pl Overton @ngr SU514500 @xy (24.18,28.99)
@pl Petersfield @ngr SU744235 @xy (34.18,18.56)
@pl Romsey @ngr SU351212 @xy (19.61,15.98)
@pl Stockbridge @ngr SU355351 @xy (18.59,21.29)
@pl Tangley @ngr SU334524 @xy (16.89,28.66)
@pl Whitchurch @ngr SU460478 @xy (22.20,28.47)
@pl Winchester @ngr SU478293 @xy (23.22,19.63)

@w 50.94 @h 37.88

@sc 6.50 @m 8

result NGR
file		 

Map speed1

  Data file: speed1.pts
Output file: speed1.ngr

OLDMAPS.exe

Plotting a NGR grid on an old map
version 4.1
MN: 12.2.1997


Given points

 no  place                    ngr         (x,y)

  1  Alton                    SU717396    (   33.20,   26.50)
  2  Andover                  SU365458    (   18.69,   25.79)
  3  Basingstoke              SU634527    (   29.56,   30.51)
  4  Bradley                  SU635418    (   32.61,   27.20)
  5  Burghclere               SU469610    (   22.08,   32.19)
  6  Buriton                  SU740200    (   33.89,   17.77)
  7  Christchurch             SZ159925    (   12.10,    2.31)
  8  Fareham                  SU575061    (   29.02,   11.29)
  9  Fordingbridge            SU150145    (   12.16,   11.58)
 10  Grately                  SU275420    (   13.92,   23.01)
 11  Havant                   SU717062    (   34.29,   11.05)
 12  Hawkley                  SU746291    (   34.51,   22.28)
 13  Kingsclere               SU525586    (   24.71,   32.46)
 14  Lymington                SZ322954    (   18.88,    5.27)
 15  Nether Wallop            SU304364    (   15.09,   21.37)
 16  Odiham                   SU740509    (   33.29,   30.60)
 17  Overton                  SU514500    (   24.18,   28.99)
 18  Petersfield              SU744235    (   34.18,   18.56)
 19  Romsey                   SU351212    (   19.61,   15.98)
 20  Stockbridge              SU355351    (   18.59,   21.29)
 21  Tangley                  SU334524    (   16.89,   28.66)
 22  Whitchurch               SU460478    (   22.20,   28.47)
 23  Winchester               SU478293    (   23.22,   19.63)
number of points = 23



Centroids of points

(x,y) centroid is  (   24.21,   21.42)
  NGR centroid is  SU491326
    numerical ngr  449.17 132.69



Map scale

scale =     2.28
scale =     2.59
scale =     2.33
scale =     1.67
scale =     2.59
scale =     2.70
scale =     2.31
scale =     2.48
scale =     2.49
scale =     2.26
scale =     2.40
scale =     2.41
scale =     2.39
scale =     2.59
scale =     2.55
scale =     2.45
scale =     2.11

map scale  1 to   238753
or         1 to   238000



Map heading

Map heading
NGR north on map is 7.4 degrees W of map north



Check points

 no  place                    ngr         map

  1  Alton                    SU717396    SU720419
  2  Andover                  SU365458    SU374447
  3  Basingstoke              SU634527    SU646525
  4  Bradley                  SU635418    SU708437
  5  Burghclere               SU469610    SU474588
  6  Buriton                  SU740200    SU709210
  7  Christchurch             SZ159925    SZ146911
  8  Fareham                  SU575061    SU574072
  9  Fordingbridge            SU150145    SU176130
 10  Grately                  SU275420    SU252395
 11  Havant                   SU717062    SU698050
 12  Hawkley                  SU746291    SU738315
 13  Kingsclere               SU525586    SU537586
 14  Lymington                SZ322954    SZ315960
 15  Nether Wallop            SU304364    SU275353
 16  Odiham                   SU740509    SU734516
 17  Overton                  SU514500    SU514506
 18  Petersfield              SU744235    SU718228
 19  Romsey                   SU351212    SU366212
 20  Stockbridge              SU355351    SU358340
 21  Tangley                  SU334524    SU340520
 22  Whitchurch               SU460478    SU465499
 23  Winchester               SU478293    SU462287



Map sheet corners

 bottom left SY852893
    top left ST968790
   top right TQ174634
bottom right TV058737



Grid lines

x positions on bottom and top edges,
y positions on left and right edges,
by which to draw lines on map

easting grid lines

Eing      bottom edge    top edge

 390          1.99          2.91
 400          6.22           1.32
 410         10.44           5.54
 420         14.66           9.76
 430         18.89          13.99
 440         23.11          18.21
 450         27.33          22.43
 460         31.56          26.66
 470         35.78          30.88
 480         40.00          35.10
 490         44.23          39.33
 500         48.45          43.55
 510         52.67          47.77
 520         56.90          52.00

northing grid lines

Ning      left edge      right edge
  80         3.96           2.63
  90          0.26           6.85
 100          4.48          11.08
 110          8.71          15.30
 120         12.93          19.52
 130         17.15          23.75
 140         21.38          27.97
 150         25.60          32.19
 160         29.82          36.42
 170         34.05          40.64
 180         38.27          44.86



Grid lines

x positions on bottom and top edges,
y positions on left and right edges,
by which to draw lines on map
SCALED x     0.65

easting grid lines

Eing      bottom edge    top edge

 390          1.31          1.90
 400          4.07           0.86
 410          6.84           3.63
 420          9.61           6.39
 430         12.37           9.16
 440         15.14          11.93
 450         17.90          14.69
 460         20.67          17.46
 470         23.44          20.23
 480         26.20          22.99
 490         28.97          25.76
 500         31.74          28.53
 510         34.50          31.29
 520         37.27          34.06

northing grid lines

Ning      left edge      right edge
  80         2.60           1.72
  90          0.17           4.49
 100          2.94           7.25
 110          5.70          10.02
 120          8.47          12.79
 130         11.24          15.55
 140         14.00          18.32
 150         16.77          21.09
 160         19.54          23.85
 170         22.30          26.62
 180         25.07          29.39



Scale line

scale line length     6.50 cm
representing    8 miles
scale 1 to   198073


Speed's Hampshire 1611, index grid
General index
Old Hampshire Mapped
Map HMCMS:KD1996.16