Researching WWI family history.

[Dianaa]

Tony

Thank you for drawing my attention to these maps. These are exactly the type of maps I'm interested in and even the information about the order of grid squares on the ebay ad explains some of the information I was lacking.

Diana

[klambie]

Might try the collection at McMaster University in Hamilton.

http://library.mcmaster.ca/maps/ww1/home.htm

[Dianaa]

Originally Posted by klambie

Might try the collection at McMaster University in Hamilton.

http://library.mcmaster.ca/maps/ww1/home.htm

Kevin

Amazing help!

Mcmaster University has a page dedicated to the map references. http://library.mcmaster.ca/maps/ww1/MapRefNo.htm

Originally Posted by Dianaa

..... In the unit diary, the grid references are further reduced to a secondary alpha numeric code. You will see a trench in grid square J 35, If I am correct this is described as J.35.B.18.82 in the diary. ...

The only remaining issue is that the McMaster references describe the last two single digits representing tenths up and across the grid square where the 19 Fld Coy RAE diary describes paired digits which I can only assume to be hundreths of the square required for the more accurate needs of the engineers.

Diana

[klambie]

You are correct, the extra digits just further subdivide the square. In WW II mapping, it's not uncommon to see three levels of subdivision, so similar for WW I would be expected.

Note that the last pair of numbers (whether single digit or two digit or more) technically define the bottom left corner of a square, not a point. Thus the object/place they are assigning coordinates to are somewhere inside that square. More digits just define a smaller square. Practically, if you ever found 3 digit numbers, that would be a small enough square to be treated like a point.