150 
Mathemati- the longest day under the one, shall exceed that under 
cal Geogra~« 
phy. 
Table of 
©limates. 
the other, by half an hour, With regard to places- 
within the polar circle, it is evident,that the el 
which comes to be wholly above the circle of illumina- 
tion, half a month before the sun reaches the summer, 
solstice L, or two months and a half after he passes Q, 
will continue to be a month above the circle, viz. half 
a month before the sun reaches L, and half a month 
till he returns to the same position. In like manner, 
the parallel that begins to be wholly illuminated one 
month before the sun reaches the solstice, or two months 
after the vernal equinox, will continue to be so for two 
months, and so of others. As the pole rises above the 
tircle of illumination at the equinox, or three menths 
before the solstice, it continues, as was formerly ob- 
served, to be illuminated for six months. Hence, be- 
tween the polar circles and the poles, six parallels may 
be found such, that the longest day under the one, shall 
be a month longer ‘than under the other. The same 
reasoning will apply to the southern hemisphere du- 
ring the sun’s progress from Q to h; and, in general, it 
is to be observed, that at any time, the length of the 
day, at a given latitude in one hemisphere, is always 
equal to the night, at the same latitude in’ the opposite 
hemisphere. The climates, as above defined,’ are con- 
tained in the following Table, where the first column 
shews the number of the climate, the second the length’ 
of the day under the highest parallel, or that nearest 
the pole, the third the latitude of that parallel) and 
the fourth the breadth of the climate. 
Table of Climates. 
Between 
the Longest Day Latitude Breadth 
Equator under the of the of the 
and highest Parallel. | highest Parallel Climate. 
Polar Circle, 
Hours. Min, Deg. Min. Deg. Min, 
1 12 30 8 34 8. 34 
2. 13... °0 16 43 8 9 
3 13 30 24 10 7 Si 
4 14 O 80 46 6 36 
1a 14 30 36 28 5 42 
6 16 ‘<0 41 21 4 53 
7 15 30 45 29 4 8 
8 146 60 48 59 8 30 
9 16 30 5) 57 2 58 
10 Li? O 54 28 2 31 
11 17 30 56 36 2 8 
12 igs O 58 25 1 49 
13 18 30 59 57 1 32 
14 19 O 61 16 1 19 
15 19 30 62 24 T'S 
16 20 640 63. 20 0 56 
17 20 30 64 8 O 48 
18 21 0 64 48 Oo 40 
19 21 30 65 20 0 32 
20 22. O 65 46 O 26 
21 22 30 66 6 0 20 
22 23 O 66 <0 oO 14 
23 23 30 66 28 0 8 
24 24 O 66 32 O 4 
GEOGRAPHY. 
Between i; uF ; 44 ; 
P Longest Day Latitude | Breadth 
Polar Circle under the of the — of the © 
bah the highest Parallel. | highest Parallel. Climate. 
Pole. ' ; 
Months. Deg. Min, Deg. Min.) 
1 1 67, 23 QO 51 
2 2. 69 50 2 27 
3 3. 73 39 3 49 
4 4 78. 31 4 52 
5 5 84. 5 5 3404 
6 6 90. 6~O 5 S551 
Besides dividing the earth into different climates, the Other d 
ancients also employed certain terms to distinguish the visions 
inhabitants of particular countries, which it may be ‘b¢ « 
useful to notice. ‘Those who ‘Jive under the same me- ~— 
ridian and parallel of latitude, but on opposite.sides of 
the equator, were called relatively to one another An-~ Antecii 
tecti, from ays, o ite to; and oma, a habitations 
They have always the same hour of the day, but oppo- 
site seasons of the year. Those who live on the same 
side of the equator, and under the same parallel of la- : 
titude, but differ 180° in longitude, were called Perts Periz 
ecii, from meg, about ; and cima, a habitation. They 
have always the same seasons, but opposite hours of 
the day. The inhabitants of places under the same pa~ 
rallel of latitude, but on opposite sides of the equator, = 
and differing in longitude 180°, were called the Anté- Antip 
rae of — anes _— ayes {ibe 
the foot. They have always opposite hours of the day, 
as well as conte seasons ot the year. The ahetx, 
tants of the different zones were also distinguished ac. 
cording to the projection of their shadows. Thus the 
inhabitants of the torrid zone were called Amphiscii, 
from «n9:, around; and cxie, a shadow ; because their 
shadow is projected sometimes towards the north, and 
at other times towards the south; or Ascii, from «, witha 4 
out; and cx; because they sometimes have no sha- 
dow. The inhabitants of the temperate zones were 
called Heteroscii, from iceges, different, and cxim; bex Hete 
cause their shadows are always projected in opposite 
directions, or towards the poles. And the inhabitants : 
of the frigid zones were named Periscii, from segs; Peri 
about, and cz ; because during their longest day, their | 
shadows describe a circle round them. : mf 
As the celestial sphere, in its apparent revolution, Differ 
may present itself under three different aspects, ac~ positio 
cording to the situation of the observer, it becomes ne- of the 
cessary to distinguish them by particular names. Ac- *P"*™ 
cordingly, to an observer at the equator, the celestial 
sphere is said to be right, because the equinoctial and Right 
parallels of declination, or circles described by the hea- 
venly bodies, are at right angles to the horizon, and di- 
vided by it into two equal parts. To an observerbe- | 
tween the equator and the pole, the sphere is oblique, Obliqu 
because the equinoctial and parallels of declination are 
inclined to the horizon, so all heavenly bodies not 
in the equator, ‘are above and below the horizon dur- 
ing unequal periods. And from the pole the sphere ap- 
pears parallel, the equinoctial coinciding with the ho- Paral 
rizon, and the heavenly bodies revolving in circles pa- 
rallel to. it. 
In the view that we have hitherto taken of the earth, Dimer 
we have considered it merely as a spherical body, with- of the 
out any regard to its actual pee and dimensions. ©" 
All the phenomena, indeed, which we have yet no- 
ticed, depend entirely on the figure and situation of the 
