SQU 
in most instances solitary wanderers through 
the ocean, but in some species are gregari- 
ous. Tliey contain large quantities of oil, 
and their skin is convertible to several use- 
ful purposes. There are thirty-four species. 
The following are the most entitled to atten- 
tion. S. carcharios, or the white shark, attains 
sometimes the length of thirty feet, and is 
the most fierce and rapacious inhabitant of 
the ocean, in the depths of which, particu- 
larly in the warmer latitudes, it principally 
ranges. According to some writers, a man, 
and even a horse, has been found entire in 
the body of one of these animals ; and the 
teeth of this, or some larger species, are ex- 
hibited in the British Museum, four inches 
and a half in depth. The intestines of this 
animal, generally, contain a vast number of 
tape worms, which may account, in some 
degree, for its peculiar voracity. 
S. maximus, or the barking shark, is 
about the size of the former, and is often 
seen near the Hebrides in small shoals of 
six or eight, but generally in single pairs. 
These have nothing of the fierceness of the 
former species, and will suffer themselves 
to be handled without resistance. They 
subsist on sea-weeds, and their stomachs 
have never exhibited indications, on being 
opened, of any other substances. They 
often sport about the billows with great 
agility and appearance of delight, and will 
suffer a boat to approach them so nearly, 
that the harpooner may pierce them with 
the instrument in his hand. But it is stated 
that the wounds thus inflicted often excite 
at first no symptom of pain, and that in 
some cases no appearance of this is indicated, 
tiff the combined efforts of two men have 
urged the instrument to its fullest depth, 
when they exhibit extreme agitation and 
rapidity, traversing the water with the most 
turbulent movements, and summoning into 
exercise, for many hours, all the skill and 
energy of those engaged in this critical pur- 
suit. See Pisces, Plate VI. fig. 1. 
S. glaucus, or the blue shark, is the most 
sC»u 
elegantly shaped and coloured of all the’ 
species, is about ten feet long, and found iit 
almost every sea. In the season for pil- 
chards it abounds on the coasts of Corn- 
wall, and is often taken with large iron 
hooks. 
S. stellaris, or the greater spotted dog- 
fish, is a native of the seas of Europe. It 
seldom exceeds in length six feet. Its snout 
is considerably elongated, whence it de- 
rives its designation of the dog-fish. It is 
found chiefly in rocky situations, and preys 
upon various shell-fish. It produces nine- 
teen at a birth, but does not appear ex- 
tremely abundant. Its flesh is eaten, and 
its skin is an article of commerce. 
S. zygaena, or the hammer-headed shark, 
is sixteen feet long, and inhabits the Medi- 
terranean and Indian seas, where its depre- 
dations are incessant £&d most formidable. 
It is distinguished by its head being'dilated 
on the sides to an extraordinary extent, 
and by the eyes being at the extremities of 
these sides. 
S. squatina, or the angel fish, is distin- 
guished by a large and flat head, rounded 
in front, is found in the European seas, and 
grows to the length of seven feet. It is 
highly fierce and formidable. 
SQUALL, in naval language, is a sudden 
violent gust of wind usually occasioned by 
the interruption and reverberation of the 
wind from high mountains. Squalls are 
very frequent in the Mediterranean, parti- 
cularly in the Levant, and are supposed to 
be produced by the new direction which 
the wind meets with in its passage between 
the various islands of the Archipelago. 
SQUARE, in geometry, a quadrilateral 
figure, both equilateral and equiangular. 
To find the area of a square, seek the 
length of one side ; multiply this by itself, 
and the product is the area of the square. 
Square number, the. product of a number 
multiplied into itself. Thus 4, is the product 
of g multiplied by 2 ; or 16, the product of 
4 multiplied by 4, are square numbers. 
The series of square integers, is l, 4, 9, 16, 25, 36, &c ; 
which are the squares of 1, 2, 3, 4, 5, 6, &c. 
Or the square fractions i, f, J, -||, ||, &c. ; 
which are the squares of. ^, |, i, -J, |, &c. 
A square number is so called, either be- 
cause it denotes the area of a square, whose 
side is expressed by the root of the square 
number ; as in the annexed square, which 
consists of nine little squares, the side being 
equal to three ; or else, which is much tlie 
same thing, because the points 
in the number may be ranged 
in the form of a square, by 
making the root, or factor, the 
side of the square.. 
