PHYSICAL ANTECEDENTS OF SCIENCE in

intimated, we require to know something of the order and

condition of that special mechanism the actions of which

so nearly concern us.

To appreciate correctly human thought, it is also necessary

to know something of the psychical powers of living creatures

which are not human. Some adequate notion as to man's

place in nature cannot be dispensed with by anyone who

would estimate at their just value the products of human

thought. We have already enumerated the sciences which

deal with living things,* and probably no one will dispute

the assertion that man, corporeally considered, is a kind

of animal, and that the sciences which relate to animals

generally relate, therefore, to him also.

The multitude of species which compose what is called

the " animal kingdom " is so vast that it would be impossible

to study them otherwise than by classifying them in a

number of more and more subordinate groups, each of

which is defined by an enumeration of certain structural

characters which the creatures included in such group possess

in common. It is usual to divide the animal kingdom into

two great groups, the lower of which is made up by creatures

the whole body of each of which is composed of a single cell

or, at most, a few cells only. Of these creatures, animalcules

of various kinds, it is not necessary for our present purpose

to say more than a few words. One kind, the Anuzba, may

here be mentioned, as it is so often referred to as closely

resembling certain particles (known as the colourless cor-

puscles) in human blood. It is a microscopic creature,

consisting of a minute piece of " protoplasm," with some

internal modifications, which protrudes parts of its body in

the form of short blunt projections, and feeds by engulfing

what it preys on into its body at various parts of its surface.

The Bell-animalcule, or Vorticella, may also be referred to

* See Chapter II., pp. 24 and 31.

intimated, we require to know something of the order and

condition of that special mechanism the actions of which

so nearly concern us.

To appreciate correctly human thought, it is also necessary

to know something of the psychical powers of living creatures

which are not human. Some adequate notion as to man's

place in nature cannot be dispensed with by anyone who

would estimate at their just value the products of human

thought. We have already enumerated the sciences which

deal with living things,* and probably no one will dispute

the assertion that man, corporeally considered, is a kind

of animal, and that the sciences which relate to animals

generally relate, therefore, to him also.

The multitude of species which compose what is called

the " animal kingdom " is so vast that it would be impossible

to study them otherwise than by classifying them in a

number of more and more subordinate groups, each of

which is defined by an enumeration of certain structural

characters which the creatures included in such group possess

in common. It is usual to divide the animal kingdom into

two great groups, the lower of which is made up by creatures

the whole body of each of which is composed of a single cell

or, at most, a few cells only. Of these creatures, animalcules

of various kinds, it is not necessary for our present purpose

to say more than a few words. One kind, the Anuzba, may

here be mentioned, as it is so often referred to as closely

resembling certain particles (known as the colourless cor-

puscles) in human blood. It is a microscopic creature,

consisting of a minute piece of " protoplasm," with some

internal modifications, which protrudes parts of its body in

the form of short blunt projections, and feeds by engulfing

what it preys on into its body at various parts of its surface.

The Bell-animalcule, or Vorticella, may also be referred to

* See Chapter II., pp. 24 and 31.