Guess the Place

[johnfilmer]

Was it a NatWest bank? Just guessing as you searched those for the Gillingham GTP.

[John Walker]

That also looks like a bank somewhere.

It was a bank once upon a time.

[MartinR]

That also looks like a bank somewhere.

[John Walker]

I don't know why but creeks always give me the jitters.  What lies beneath and all that  .   Looking at the chart I think I would find navigating waters like that a nightmare.


Right - next GTP.


Where is this door?

[MartinR]

OK, a bit of technical information on charts here, just in case anyone is interested.:

A chart will always show the latitude and longitude since that is how navigation is done.  It is crucially important that the latitude scale running down both sides is used and never the longitude scale across the top and bottom.  The lines of longitude (NS) converge at the poles and so will never be 60 nm apart except at the equator.  Most charts will not show nautical miles, you just read from the longitude scale.  Furthermore, the scales are in degrees, minutes and decimals of a minute.  Positions are given in this way too.  One minute is a nautical mile, 1/10 of a minute is a cable's length and 1/1000 of a minute is a fathom (6' or 2m).  For instance one of the navigation buoys in the mouth of the Medway is at 51°25'.813N, 000°43'.945E.  Note also that the latitude is always given as two figures (ie 00 to 90) whereas the longitude is given as three figures (ie 000-180).

See any book on navigation at Day Skipper level or above.

I've enclosed a tiny part of one chart showing Walton Creek, Essex.  Notice on the right hand side 51°52'N and 51'.5.  The second, lower value is minutes only and the "ticks" are tenths of a minute, near enough 600'.  Notice also the ticks across the bottom are much closer than down the sides.  The figures in the water are depths in metres and tenths (in smaller type).  Underlined values are drying heights.

[Dave Smith]

Thanks from me too Martin. Interestingly, where I worked in 1960+, the Research manager was on the British Metrics Committee, changing everything to SI units. He said at that time that Meters & Millimeters were the standard, not Centimeters. Of course the nautical mile ( knot = n/m per hour)is relative to the division of the earth into degrees, minutes & seconds, so is more logical than meters.

[John Walker]

Really interesting info MartinR. You obviously know your maps. Thank you.

[MartinR]

Dave, John's reply gives the game away in this particular case: 123.94 feet = 123' 11" and the spot height is 121' ± 6".  As regards a date, the "one inch" seventh series (1:63360) maps were in imperial units and were issued up to 1962.  Starting from 1974 the Landranger series of 1:50000 maps were issued in metric units.

However in one important way OS maps have always had an element of metric in them, the National Grid is entirely metric.  A grid reference such as the waterworks: TR 24307 55335 first identifies a 500km by 500km square known as "T", then within that the 100km by 100km square known as TR.  The two numbers represent 24.307 km east of the square's bottom left and 55.335 km north of the bottom left.  They define a 1m² square.

There's a Wiki entry on benchmarks at https://en.wikipedia.org/wiki/Benchmark_(surveying)

Oh, and if you think this is problematic, maritime charts used to show heights above sea level (eg bridges, chimneys) in feet but depths in fathoms (1 fathom = 6').  Now they are all metric, except of course that they use lat/long as a grid and everyone uses nautical miles and cables for distance!

[John Walker]

This might help ...


Elevation of Gillingham, UK


Longitude: 0.551438   Latitude: 51.386322   Elevation: 38m / 125feet

[Dave Smith]

MartinR. As you have a knowledge of all things associated with maps, at what stage does the benchmark change from inches- e.g. 123.94"- to feet & inches please? BUT, as that is only 10ft 3.94" & I'm sure Gillingham High Street is higher that that above msl, maybe it's 123ft & ?" I know that this is a little off topic but still relevant &, like John Walker, I find all these threads interesting.

[John Walker]

That's more info I've learned from the GTP threads.  Thanks, Stuartwaters, MartinR, and CAT.


I had to work for this one.  Worked my way through NatWest banks on GSV.  Found it around the 10th try.


Next one up after discussion on benchmarks etc.

[CAT]

Worth baring in mind that when looking at Bench marks on old maps they will be marked in feet and inches as opposed to the more recent maps which are in metres and centimetres. joys of metrification.

[MartinR]

Stuart, that is a surveyor's benchmark, not a WD boundary marker.  The WD symbol doesn't have the line across the top.  Looking at an old 1960s map (attached) you can see it shown as an arrow against the bank's wall and the legend "BM 123.94" gives the precise height of the deepest part of the horizontal cut.  Incidentally, the cross and "121" is a spot height that isn't marked but just added to make understanding the terrain easier.

[stuartwaters]

JW you have it, well done.


That branch of Natwest is infamous for those of us of a certain age. Way back in the mid-80s, a fight had started in a trendy pub/nightclub called "Kents", formerly the Kent Arms on the corner of Jeffrey Street and James Street. The fight spilled over onto the street and into Gillingham High Street and somebody was stabbed to death outside the Bank. Kents closed soon after due to a lack of customers and is now a Chinese Takeaway.


I had no idea that the War Department owned land into Gillingham High Street (I'm assuming that is a War Department boundary marker carved into the stone).


 I thought that might go a little longer. Over to you....

[John Walker]

NatWest Bank, Gillingham High Street ?