The Angry Corrie 21: Jan-Feb 1995
Rum, Sanday and the cash
I draw your attention to OS Sheet 39, Rum and Eigg: a rip-off even greater than Sheet 12. Of its 1600 grid squares, it has 1180 to call its own, losing 300 squares of southern Skye and north Rum to Sheet 32, and 120 squares of Ardnamurchan shoreline to Sheet 47. Of these 1180, a whopping 978 contain nothing but blue blue sea. The displaced rock bump of Oigh-sgeir I shall ignore, as it doesn't belong here anyway - although I do include the rock of Sgeir Charrach sitting proudly in NM5873, even if it does look a lot like a squashed midge.
This leaves 202 squares containing something terrestrial, or 12.6% of the total. Of these 202, a mere 70 are fully occupied. 12.6% of £4.25 is 54p. 70 squares comprise 4.3%, or 18p!
Damn things in the sheets
Needless to say, Sheet 39 represents the pinnacle of OS intelligent marketing:
"Packed full of information" - inside map cover.
"...excellent value" - OS trade brochure. (Price increase imminent.)
Still, Sheet 39's 202 squares are a good deal more interesting than all 1600 squares of any East Anglian sheet. (Not sure if Prospect would agree with that! - inclusive Ed.)
The land area covered by the OS National Grid is around 230000km**2. One 40km x 40km sheet represents 1600km**2. Therefore the theoretical minimum number of sheets required is 145.