1069536r
And Because the navigation & stirradge is made commonly by the
common compasse whose wires stand half a poynt
to the Eastwards of the North of the fly. It is necessary
that you also know the variation of this compasse,
otherwise sayling by such a compasse, you can make
no ture true reckoning of your course, nor
appoynt what stirradge ought to be
common compasse whose wires stand half a poynt
to the Eastwards of the North of the fly. It is necessary
that you also know the variation of this compasse,
otherwise sayling by such a compasse, you can make
no ture true reckoning of your course, nor
appoynt what stirradge ought to be
I shall I will therefore geve this severall rule: having
noted the variation of the wires or north poynt byof one of the former
rule & observation compasses which some call Meridionall
compasses; you shall find the variation of the north poynt
of the common compasse thus: Reckon so many degrees
as you former variation contrary wise to to the contrary
way of the digit denominations
noted the variation of the wires or north poynt byof one of the former
rule & observation compasses which some call Meridionall
compasses; you shall find the variation of the north poynt
of the common compasse thus: Reckon so many degrees
as you former variation contrary wise to to the contrary
way of the digit denominations
ffirst in that compasse that hath the moveable fly; move
it in such sort that his north poynt stand to the northward
of the wires half a poynt; then must the wires be to the east-
wards so much, & so that fly representeth the common
it in such sort that his north poynt stand to the northward
of the wires half a poynt; then must the wires be to the east-
wards so much, & so that fly representeth the common
After reckon the degrees of your former variation from the
wires contrary to the denomination; that is to say if
the variation were East, reckon northward; or if west
reckon Eastward & where the degrees ened there is the
true north of the world; which being marked you may
then see both hos much & wh which way the North of the
grand inner fly or common compasse doth
wires contrary to the denomination; that is to say if
the variation were East, reckon northward; or if west
reckon Eastward & where the degrees ened there is the
true north of the world; which being marked you may
then see both hos much & wh which way the North of the
grand inner fly or common compasse doth
You may also do the same by that compasse which hath no
moveable fly, or by any such it is
drawne in any booke
so it hath degrees be devided into degrees & that you make
a pricke or note half a poynt to the westwards of the north
to represent the north of your common
moveable fly, or by any such it is
drawne in any booke
so it hath degrees be devided into degrees & that you make
a pricke or note half a poynt to the westwards of the north
to represent the north of your common
But of whether our compasse degrees or no degrees are may helpe your
self by addition & subtraction, remembring that 11 degrees
& a quarter make a poynt & 5 degrees & a half & half a quarter
do make half a
self by addition & subtraction, remembring that 11 degrees
& a quarter make a poynt & 5 degrees & a half & half a quarter
do make half a
The example of this need be but short: The wires in the former
observation varied to the eastward 9 degrees & a half. halfe a
poynt to the northwards is the north of the common compasse; therefore abate
it out of . there will remayne 4 degrees had & so much doth your
common compasse vary in that plane; & to the being lesse then half a poynt
& to the eastwards as before bycause of the the half poynt was lesse
then the variation of the
observation varied to the eastward 9 degrees & a half. halfe a
poynt to the northwards is the north of the common compasse; therefore abate
it out of . there will remayne 4 degrees had & so much doth your
common compasse vary in that plane; & to the being lesse then half a poynt
& to the eastwards as before bycause of the the half poynt was lesse
then the variation of the
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