AST 
Arabians call it in their tongue ajlharlab\ a word formed 
by corruption from the common Greek name. This name 
was originally uled for a fyftem or aflemblage of the Seve¬ 
ral circles of the fphere, in their proper order and fitua- 
tion with refpeCt to each other. And the ancient intern¬ 
ments were much the fame as our armillary fpheres. The 
firft and mod celebrated of this kind, was that of Hip¬ 
parchus, which he made at Alexandria, the capital of 
Egypt, and lodged in a feenre place, where it ferved for 
divers agronomical operations. Ptolemy made the fame 
ufe of it: but, as the inftrument had feveral inconve¬ 
niences, he contrived to change its figure, though perfectly 
natural, and agreeable to the doCtrine of the fphere ; and 
to reduce the whole aftrolabe to a plane furface, to which 
he gave the name of the planifphere. Hence, aftrolabe is 
ufed among the moderns for a planifphere, or a ftereogra- 
phic projection of the circles of the fphere upon the plane 
of one of the great circles; which is ufually either the 
plane of the equinoctial, the eye being then placed in the 
pole of the world ; or that of the meridian, the eye being 
fuppofed in the point of interfeCtion of the equinoctial and 
horizon ; or on that of the horizon. 
Astrolabe, or Sea Astrolabe, more particularly 
denotes an inftrument chiefly tiled for taking altitudes at 
fea; as, the altitude of the pole, the fun, or the ftars. 
The common altrolabe, reprefented by the annexed figure, 
confiics of a large brafs ring, 
about fifteen inches in dia¬ 
meter, whofe limb, or a con¬ 
venient part of it, is divided 
into degrees and minutes. It 
is fitted with a moveable la- 
bel or index, which turns 
upon the centre, and carries 
Dtwo fights; having a fmall 
ring, at A, to hang it by 
in time of obfervation. To 
make ufe of it in taking al¬ 
titudes ; fufpend it by the 
ring A, and turn it to the 
fun, &c. fo as that the rays 
may pafs freelv through both the fights F and G; then 
will the label cut or point out the altitude on the divided 
limb. The aftrolabe, though now grown into difufe, is 
by many efteemed equal to any other inftrument for taking 
the altitude at fea ; efpecially between the tropics, where 
the fun comes near the zenith. 
ASTRO'LOGER, /. [ajlrologus, Lat. from on and 
Gr.] One that, fuppofing the influences of the ftars 
to have a cafiial power, profefles to foretel or difeover 
events depending on thofe influences.—A happy genius is 
the gift of nature : it depends on the influence of the ftars, 
fay the ajlrologers ; on the organs of the body, fay the na- 
turalifts; it is the particular gift of heaven, fay the di¬ 
vines, both chriftians and heathens. Dry den. —It was 
anciently ufed for one that underftood or explained the 
motions of the planets, without including prediction.—-A 
worthy ajlrologer , by perfpeCtive glades, hath found in the 
ftars many things unknown to the ancients. Raleigh. 
ASTROLO'GIAN, f. The fame with ajlrologer. 
ASTROLO'GIC, or Astrolo'gical, adj. Profefting 
aftrology. Relating to aftrology.—The poetical fables are 
more ancient than the ajlrological influences, that were not 
known to the Greeks till after Alexander the Great. Bentley. 
ASTROLO'GIC ALLY, adv. In an aftrological manner. 
To ASTRO'LOGIZE, v. n. To praClife aftrology. 
ASTRO'LOGY,/. The art of foretelling future events,, 
from the pofitions, afpeCts, and influences, of the heavenly 
bodies. The word is compounded of a ftar, and 
&oyos, a difeourfe ; whence in the literal fenfe of the term, 
aftrology fliould fignify no more than the doElrine or fcience 
of the ftars ; which indeed was its original acceptation, and 
conftituted the ancient aftrology ; which confided formerly 
of both the branches now called aftronomy and aftrology, 
.under the name of the latter only j and for the fake of 
Yol. II. No. 73. 
AST 309 
making judiciary predictions it was, that aftronomical ob- 
fervations, properly fo called, were chiefly made by the 
ancients. And though the two branches be now perfect¬ 
ly feparated, and that of aftrology almoft univerfally re¬ 
jected by men of learning, this has but lately been the 
cafe, as their union fubiifted, in fome degree, from Pto¬ 
lemy till Kepler, who had a.ftrong bias towards this licence. 
Aftrology may be divided into tw o brandies, natural or me¬ 
teorological, and judiciary. 
To natural or meteorological aftrology belongs the pre¬ 
dicting of natural effeCts ; fitch as the changes of weather, 
winds, itorms, hurricanes, thunder, floods, peftilences, &c. 
But this art properly belongs to phyfiology or natural philo- 
fophy ; and is only to be deduced, d pojleriori, from pheno¬ 
mena and obfervations. And for this department of as¬ 
trology it is that Mr. Boyle makes an apology in his Hiftory 
of the Air. 
Judicial, or judiciary aftrology, which is what is com¬ 
monly underftood by ajlrology, is that which profefles to 
foretel moral events, or fuch as have a dependence on the 
fate and fortune of man; as if they were produced or di¬ 
rected by the ftars. The profeflors of this kind of aftro¬ 
logy, in effeCt, maintain, “ That the heavens are one great 
volume or book, wherein God has written the hiftory of 
the world; and in which every man may read his own def- 
tiny, and the tranfactions of his time. The art, fay they, 
had its rife from the fame hands as aftronomy itfelf: while 
the ancient A (Tyrians, whofe ferene unclouded iky favour¬ 
ed their celeftial obfervations, were intent on tracing the 
paths and periods of the heavenly bodies, they difeovered 
a conftant fettled relation of analogy, between them and 
things below; and hence were led to conclude thefe to be 
the pares, the deftinies fo much talked of, which preiide 
at our births, and difpofe of our future fate. The laws 
therefore of this relation being afeertained by a feries of 
obfervations, and the firare each planet has therein; by 
knowing the precife time of any perfon’s nativity, they 
were enabled, from their knowledge in aftronomy, to erect 
a fcheme or horofeope of the fituation of the planets at 
that particular point of time; and hence, by coniidering 
their degrees of power and influence, and how each was 
either ftrengthened or tempered by fome other, to compute 
what would probably be the refult thereof.” 
Judicial aftrology, it is commonly faid, was invented in 
Chaldaea, and from thence tranfmitted to the Egyptians, 
Greeks, and Romans; though fome infift that it was of 
Egyptian origin, and aferibe the invention to Cham. But 
it is to the Arabs that we owe it. At Rome the people 
were fo taken with it, that the aftrologers, or, as they were 
then called, the mathematicians, maintained their ground 
in fpite of all the edicts of the emperors to expel them 
out of the city. Among the Indians, the bramins, who 
introduced and praClifed this art in the eaft, have hereby 
made themfelves the arbiters of good and evil hours, 
which gives them great authority : they are confulted as 
oracles, and they fell their anfwers at good rates. 
The fundamental principle, therefore, on which the fci¬ 
ence or doCtrine of aftrology feems to depend, is founded 
on the fuppofed influence of certain afpeCts, formed by the 
principal ftars and planets with the earth ; which afpedts, 
being either of a benign or malignant quality, are accord¬ 
ingly fuppofed to temper and influence the ambient with 
their rays; and, by their configurations with the fun and 
moon, to aCt both upon the fruit of the womb, and upon 
all fubftances, animate or inanimate, upon which the am¬ 
bient or elementary matter, thus faturated and prepared, 
can pofiibly be fuppofed to fall. In the ancient aftrology 
only five afpeCts were materially regarded, namely, con¬ 
junction, fextile, quartile , trine, and opposition. Conjunction 
is denoted by this character , and is when the planets arc 
in the fame fign and degree, or have the fame longitude. 
Sextile is denoted by ajs, and is when the planets are did 
tant by the fixth part of a circle, or two figns or fixty de¬ 
grees. Quartile is denoted by □, and is when the planets 
are diftant one-fourth of the circle^ or ninety degrees, or 
4 K tlu-ee 
