DIAL. 
index, when the firft meridian gocs off the ee at hi 
horizon, both in the forenoon and afterno ay down 
thefe hoursdiftance 0 on the dial plane, lee i dividing a 
{femicircle into tw 
XII, o 
Dist. As the fubftyle makes an — with the meridian 
line in this kind of dials, falling am 
lines in an eaft decli 
that degree of declination where the reckoning ends; 
turn the globe till the firft meridian cuts the aaron in File 
rom the fouth 
that declination from the eaft point ‘of the horizon towards 
the fouth, and bring the quadrant of altitude to the degree 
in the ho-izon at which the reckoning ends; both for finding 
the forenoon hours, and diftance of the fubsty! e from the me- 
ridian; ard for the afternoon hours bring the quadrant to the 
oppolite degree in the horizon, as far from the weft towards 
the north ; and then proceed as above. The north dial de- 
.clining eaft or weft by the fame number of degrees may be 
eafily had from the former, by only extending the hour- lines, 
ftyle, and fubftyle, quite through the centre; for thus the 
fouth-eaft decliner wi ill produce the north- “welt decliner, 
and the fouth-weft decliner the north-eaft decliner. Fergufon, 
_ ae 
draw a rece ete declining from the north towards 
the 79 and weft.— e declination of the planes, as al- 
ready taught ; as no ok dials are only fouth dials in- 
verted, draw a vertical dial declining from the fouth, an 
Invert iti a manner, as that the centre C looks to the 
et ards ts ontrary- 
wif ini: all sue mee re infuch a pune cannot be 
For the practice, the beit way is, after drawing a fouth de- 
a upon paper, to prick the feveral points thereof through 
a pin; then applying the face of the paper to the wall, 
the back fide thereof will fhew you all the points neceffary 
for the north declining dial. 
Diacs, Juclined, are thofe drawn on planes not ereét, 
inclining, or leaning forward towards the fouth, or fouthern 
fide of the horizon, in an angle, either greater or lefs than the 
equinoétial plane. 
Such an inclined plane may be conceived by fuppofing one 
part of the plane of the equator lifted up towards the ze- 
nith, and the other deprefled towards the nadir ; and thus to 
revolve upon a line drawn from the eaft to the weft point of 
the horizon. 
Diat, To draw an inclined. 1. The inclination of the plane 
as DC (fg. 23.) being found by adeclinator, as taught un- 
if it fall feta ae the i Saar plane 
CE, and the vertical one C B, in ner as that the 
ngle of ae is grote eee the elevation of 
the equator E C A; on the upper fide lel a Peas dial, and 
n th ine dial, to an elev equator, 
h of t 
which is equal to the aggregate of the en of the equa- 
tor of the given place, and the complement of the inclination 
toa quad 
2. If the inclined plane CF fall between the horizontal 
and the en inocti E, fo 
. 
) 
co 
so 
Ps) 
ot 
et 
a 
a) 
=] 
a 
tay 
° 
eh 
ne 
inclination es CA, 
ECA, defcribe an “horizontal dia 
pole, equal to the aggregate o 
the given place, and the Catan _ the pla 
inclined, are drawn after the fam ner as pane dials ; 
except, that the index in the ace cafe muft be fitted un- 
the line of contingency, in the former cafe, is DC, and in 
the _. er FC, 
1A peal are thofe drawn on planes not ereét, but 
a or Jea backw 
pofing one Hae t of the polar 
plane raifed towards the zenith, and the er depreffed to- 
wards the nadir; and thus revolving aie a line drawn 
from eait to weft. To find the reclination of a plane, fee 
RECLINATION. 
Dia, To draw a reclining. 1. If the reclined plane HC 
fall between the vertical plane BC, and the polar plane IC, fo 
as that the angle of reclination BCH i s lefs than the 
° 
oh 
fad 
a 
ta) 
572 
< 
a 
=] 
~~ 
— 
i 
QO 
om 
- 
rt) 
3 
OQ. 
et 
load 
oO 
oY] 
Bb 
ge 
ao 
° 
ta) 
=t 
oO 
OQ 
m 
=] 
2 
=. 
° 
3 
N 
nation BC K is cee than the diftance of the pole from 
the zenith IC B, defcribe an horizontal dial thereon to an 
elevation of the pole, equal to the difference between the 
angle of reclination, and the elevation of the equator of the 
given place pe 
T)1 Sas 77. —The 
inclination and reclination of the ae ine, and the elevation of 
the pole, being o find the angles made in the cen- 
tre of an ere or eons dial, by the meridian and hour 
— 
= 
= 
= 
mo 
Such dial is properly an horizontal dial, fora latitude equal 
to the particular elevation of the pcle on the plane of the dial. 
Its angles, therefore, are found by the canon laid down for 
orizontal diaie 
sto the elevation of the pole on the foe plane, it is thus 
found: the plane being inclined, ecith s inclination is 
greater than the elevation of the pole of ue place, iv a or 
it is equal thereto. In the two firft cafes, for upper ,or 
lower north dials, the particular elevaticn of the pole on the 
plane is had by taking the difference between the elevation of 
the pole of the place, and the inclination of the plane; and in 
the latter cafe, the dial is a polar dial, wherein the hour-lines 
will be parallel, by reafon that the plane being placed on the 
axis of the world, neither of the poles can be reprefented 
thereon 
For upper north, and lower fouth dials. 1. If the 
clination be greater than the complement of ri clevating 
e complement 4f the inclination muft be added to the 
complement of ae elevation. 
nation muft be 
the dial will 
- the centre will be equal : the fun’s diftance from the 
BS 
Ls, |, Deinclined, are boos which both decline and ine 
cline, ¢ or recline. See 
The ufe of inclined, pee and efpecially deinclined 
8 dials, 
