SOR 
sometimes on vegetables. These animals 
are often observed swimming on rivers and 
lakes in large companies. On land their 
motions are particularly slow. I'hey are 
destroyed in Russia to be placed in drawers 
oi; chests, from which they effectually keep 
moths at a distance. See Mammalia, Plate 
XX. fig. 3. 
S. radiatus, or the radiated shrew, is a 
native of Canada, and is remarkable for 
having on the extremity of its snout a circle 
of sharp pointed processes, somewhat like 
the radius of a boot-spur, for having its tail 
most curiously knotted, somewhat resem- 
bling what are called Queen’s garters, and 
for having its feet with five toes, each co- 
vered with scales. It burrow's like the 
mole, but is seen far more fi eqnently above 
ground. See Mammalia, Plate XX. fig. f . 
S. cmnileus, or the perfuming shrew, is 
found in India, and is stated to leave an in- 
tolerable musky scent on every shbstance 
over which it passes, and it has been assert- 
ed by gentlemen of respectability, that a 
corked bottle of wine has been so com- 
pletely penetrated by this effluvium, as 
totally to spoil the liquor. The great 
strength and subtlety of the perfume are, 
at all events, unquestionable. This animal 
prefers rice to almost all other food, living 
chiefly in the rice fields, but occasionally 
entering houses. 
S. exilis, or the pygmy shrew, abounds in 
Siberia, is shaped and coloured like the 
common shrew, and is noticed here for 
being, probably the very smallest of Euro- 
pean quadrupeds, being about half a dram 
only in weight. See Mammalia, Plate XX. 
fig. 1. 
SORITES, in logic, a species of reason- 
ing, in which a great number of propo- 
sitions are so linked together, that the predi- 
cate ofthe one becomes continually the sub- 
ject of the next following, till at last a con- 
clusion is formed by bringing together the 
subject of the first proposition and the pre- 
dicate of the last ; such is the following ar- 
gument, “ God is omnipotent ; an omnipo- 
tent being can do every thing possible ; a 
being that can do every thing possible, can 
do whatever involves not a contradiction ; 
therefore, God can do whatever involves 
not a contradiction.” This combination of 
propositions may be continued to any length 
we please, without in the least weakening 
the ground upon which the conclusion rests; 
and the rpason is, because tlie sorites may 
be resolved into as many simple syllogisms 
as tliere are middle terms in it ; and the 
SOU 
conclusion of the last syllogism is universally 
found to be the same witli the conclusion of 
the sorites. 
, SOUND or. Hearing, sense of. The 
sense of sight is effected by rays of light, 
proceeding from the different objects to the 
retina. The sense of feeling is effected by 
the contact of its various objects with the 
body, or by the vigorous or unsound state 
of the parts of the body. The sense of taste 
is affected by certain particles of substances 
which are dissolved by the saliva, and thus 
brought into contact with the organs of 
taste. The sense of smell is affected by 
particles which various'substances are con- 
tinually sending into the air, and which im- 
press the membrane which lines the cavity 
and bones of the nose. The sense of hear- 
ing is affected by the pulsations or vibra- 
tions of the air, which are caused by its 
own expansion, or by the vibrations of 
sounding bodies. These sensations, or vi- 
brations in the air, are called sounds, as are 
also the sensations which they produce. The 
organ of hearing is much more complicated, 
and much less understood, than that of 
sight. We shall here give a very general ac- 
count of it , and refer those who wish for 
further information to the article Anato- 
my. The external ear collects and modi- 
fies sounds ; and by a long channel commu- 
nicates them to the internal ear : this con- 
sists, in the first place, of what is called the 
drum ot the ear, which is a small cavity, 
closed towards the opening of the ear by a 
delicate membrane. In the drum are three 
or four very small bones, furnished with 
muscles, and joints. From the drum are 
several openings, one of which is to the 
mouth ; the others communicate into the dif- 
ferent recesses of the ear. One of these leads 
into the labyrinth, which consists first, of a 
small irregular cavity, next of three semi- 
circular canals, and lastly of a winding spi- 
ral canal, not unlike some sea shells. All 
tliese parts of the cavity are lined with a 
very delicate membrane, and filled with 
a watery fluid, which conveys to the por- 
tions of the nerve in contact with it, the 
vibrations received from the membrane 
which separates the labyrinth from the 
drum of the ear. The vibrations of the air 
act upon the drum, and thus set in motion 
the series of small bones in the cavity of 
the drum ; these communicate the vibra- 
tions to the membrane which separates the 
drum from the labyrinth, and- this (as be- 
fore mentioned) produces vibrations in the 
watery fluid, in the several parts of the 
