Supplement to the “Colliery Guardian,’’ December 31st, 1915.	•—■-----

The “Colliery Guardian" Coalfields Map, giving the lines of Equal Magnetic Declination for January 1, 1916.

Also the Mines Inspection Districts and principal shipping ports.

Cardigan Bay

^oery^yrh

Belfasx

EDI

iflerw/cA

(TMFRIES

C ITMBERt AND

Midd/cfot

Whifhy

Hc/'\

mlngh

Grimsby

steR

CARNARVON

JMIT

SB.

Nor

MIN

Hunting

IBRI

EDFO

>RO

Monmot

.CHIN

OXFORp

BERKSHIRE

Rflcdin,

>»lu4>uty

Dorchesfei

C 0BWA1L

ROXBURGH

HEREFORD

L J - PEE BLES j X,
d O

,< f—’ sel“ikk<

mstrythe

•6RLAND

Hartle pool

prfh «f Forth

,4 Itrrrno^n
*7)

o rhau'eJ

Off AR GYL	11	>;/
		C 1 , r(  *

Town

Corrections in
Minutes of Arc.

TABLE OF LOCAL CORRECTIONS
TO BE APPLIED TO THE
MAGNETIC DECLINATION.

Edinburgh	+ 4
Kirkcaldy	+ 2
Falkirk •	.	+16
Hamilton	• — 1
Glasgow	• —11
New-Cumnock	.	— 9
Ayr	.	— 9
Whitehaven •	.	+ 7
Maryport	0
Wigton •	.	+ 2
Berwick-on-Tweed	.	—21
Morpeth	.	— 5
Newcastle	•	— 4
Sunderland -	•	—10
Durham •	-	.	.	— 9
Bishop Auckland .	•	— 4
Stockton	. — 1
Guisborough	.	— 2
Leeds	.	— 7
Pontefract	•	+ 6
Huddersfield •	•	— 4
Barnsley •	•	•	+ 4
Sheffield	.	+23
Chesterfield •	•	•	+11
Mansfield	.	+ 6
Nottingham	.	— 4/
Burnley ...	•
Rochdale	
Bolton ...	•
Wigan ...	• /— 7
St. Helen’s •	• / — 3
Manchester •	•	7 —17
Congleton	Z —13
Stoke-on-Trent • /	' -	0
Flint .	.	/	•	+ 4
Mold .	- Z	+ 3
Wrexham •/ •	•	+ 4
Shrewsbury/• •	•	+ 8
Wellington/ •	•	+ 8
Rugeley y -	.	— 6
Wolverhampton •	•	—20
WalsaX - • •	—21
Dudley- -	.	—20
Birmingham .	•	.	—23
Tamworth	-	+10
A^herstone -	.	+40
Nuneaton	.	+14
Ashby-de-la-ZouCh	.	-12
Lydney -	.	— 5
Bristol ...	•	— 3
Radstock	0
Pon ty pool	+ 3
Cardiff ...	— 5
Pontypridd -	— 6
Neath -	-	+ 4
Aberdare -	•	•	+ 4
Swansea	•	— 8
Llanelly ...	-	—10
Haverfordwest	.	—19
Dover	-10
London (Kew)	.	-’-16

		JR B
\	/a v '		

ort|ampto:

k	Y	\	. /	Bedford *
•	t"; I	
	
	•\BuckmgMijn \	\

n e /	-j		3 OVER SET/,

THE EXPOSED & HIDDEN COALFIELDS

OF THE

UNITED KINGDOM

English Miles, 24-7 Miles, to omc Ihlh
‘M j—4°.-r- r t.







Zin the above map the EXPOSED COALFIELDS are shewn by blue washes. The strong blue shade lines indicate PROVED HIDDEN COALFIELDS, the weak blue shade lines representing possible extensions. No attempt is
made to indicate either^the extent of the HIDDEN COALFIELDS in the BRISTOL area, or the limit*of the DOVER COALFIELDS. Other possible concealed areas are too hypothetical to delineate.

RAILWAYS are shewn in red. The chief COAL EXPORTING TOWNS are printed in red, and thoseTOWNS POSSESSING A MINING UNIVERSITY OR COLLEGE approvedjunder the Coal Mines Act 1911, are in black capitals.

The Isogonals or LINES OF EQUAL MAGNETIC DECLINATION are laid down for January 1, 1916. The lines are mean lines, and considerable local deviations are found to exist, particularly in the Birmingham district. For any
case in which greater accuracy is required, reference should be made to the TABLE OF LOCAL VARIATIONS IN DECLINATION inserted as an inset, which gives the amounts of deviation from the mean values indicated by the
isogonals at a^number of "places fairly evenly spread over the mining districts according to the last magnetic survey. Corrections shewn + are to be added to the Declination as determined from the map and those shewn — are to be
subtracted. Corrections for places not mentioned in the table may be obtained by taking proportional distances from the two nearest towns given. The Magnetic Declination was diminishing at the average annual rate of 9 minutes
during 1914, but the diminution was not uniform for all parts of the Kingdom.