ATJG 
which sometimes visit us from countries still 
farther north, prove that nature has not 
confined her works of elegance to regions 
within the tropics. 
The whole class of birds differs essentially 
from all other animals in internal structure, 
as well as in external form and appearance ; 
and every point of difference, when accu- 
rately examined, is evidently adapted to 
their peculiar liajrits. These will be no- 
ticed under the several orders and genera. 
To give but a single instance in this place : 
the accipitres have sight so piercing, that 
frequently, when so high as to be out of 
human ken, they can descry their prey up- 
on the ground, and their flight is so rapid, 
that they can dart upon it with the celerity 
of a meteor. Their prey varies according 
to their strength and rapacity, from the 
lamb or kid, which the vulture bears away 
in his talons, to the smaller birds and mice, 
on which the hawk and owl tribes feast. 
To prevent the depredation that these 
would otherwise commit, nature has or- 
dained that this tribe of birds should be the 
least prolific ; few of them lay more than 
two eggs. 
AUGEA, in botany, a genus of the De- 
eandria Monogynia class and order. Calyx 
five-parted ; corolla o ; nectary ten-toothed ; 
capsule ten-celled. One species, a native 
pf the Cape. 
AUGITE, a mineral of the Chrysolite fa- 
mily, found in basalt, sometimes in grains, but 
most commonly in crystals, mostly small 
and complete. Colour blackish green, some- 
times passing into leek green, and rarely to 
liver brown. Specific gravity 3.22 to 3.47. 
Before the blow-pipe it is with difficulty 
converted into a black enamel : the consti- 
tuent parts are 
Silica 52.00 
Lime. 13 20 
Alumina 3.33 
Magnesia 10.00 
Oxide ofiron 14.66 
. — manganese 2.00 
95.19 
Loss 4.81 
100.00 
It is found very abundantly in Bohemia, 
Transylvania, Hungary, Scotland, as at Ar- 
thur’s Seat, near Edinburgh, and remark- 
ably fine in the island of Roma, one of the 
Hebrides, and equally beautiful at Arendal, 
in Norway. Augite is distinguished from 
AVI 
olivino by its darker colours, different crys- 
tallization, greater hardness, and specific 
gravity. It used to be considered as a pro- 
duct of fire; but the circumstance of its 
occurring wrapped up, not imbedded in lava, 
demonstrates that it is one of the consti- 
tuent parts of the mother-stone, which has 
escaped fusion. 
AUGMENT, in grammar, an accident of 
certain tenses of Greek verbs, being either 
the prefixing of a syllable, or an increase of 
the quantity of the initial vowels. 
Of these there are two kinds, the aug- 
mentum, temporale, or of a letter, when a 
short vowel is changed into a long one, or a 
diphthong into another longer one; and 
augmentum syllabicum, or of a syllable, when 
a syllable is added at the beginning of the 
word. 
AUGMENTATION, was the name of a 
court erected 27 Hen. VIII. so called from 
the augmentation of the revenues of the 
crown, by the suppression of religions houses, 
and the office still remains, wherein there 
are many curious records, though the court 
has been dissolved long since. 
Augmentation, in heraldry, are addi- 
tional charges to a coat-armour, frequently 
given as particular marks of honour, and 
generally borne either on the escutcheon or 
a canton ; as have all the baronets of Eng- 
land, who have borne the arms of the pro- 
vince of Ulster in Ireland. 
Augmentation, in music, a term confined 
to the language of fuguists, and is the 
doubling the value of the notes of the sub- 
ject of a fugue or canon : or, the giving the 
intervals of the subject in notes of twice the 
original length. 
AUGRE, or AwcitE,an instrument used 
by carpenters and joiners to bore large 
round holes, and consisting of a wooden 
handle and an iron blade, terminated at 
bottom with a steel bit. 
AVIARY, a place set apart for feeding 
and propagating birds. It should be so 
large, as to give the birds some freedom of 
flight; and turfed, to avoid the appearance 
of foulness onthefloor. See Apis and Bees. 
AVICENA, Ebu Sina, in biography, 
has been accounted the prince of Arabian 
philosophers and physicians. He was bora 
at Assena, near Bokhara, in 978; and died 
at Hamadan in 1036, being 58 years of 
age. 
The first years of Avicena were employed 
in the study of the Belles Lettres, and the 
Koran, and at ten years of age he was per- 
fect master of the hidden senses of thal 
