A spoon is a hand tool used for transporting food to the
mouth. For convenience, in this Entry, the material to be
transported will be called the stuff.

Structure

A spoon is made up of two parts, the bowl and the handle.

The handle is designed to allow the user to support and move
the bowl in comfort, and so is usually reasonably rounded and of a size which
is easily held in the hand. Some spoons have their bowl and handle made out of
the same material, e.g. wood or metal. Many use different materials, as the
differing desired characteristics of bowl and handle can often be best met by
two different materials.

The bowl is a structure designed to provide a local area of
reduced gravitational potential, surrounded by a closed loop of greater
gravitational potential. If used in a gravitational field the bowl thus
constrains the content to remain within it unless the user imposes a force on
the content such as to produce an acceleration large enough to overcome the
gravity well. Increasing the potential difference between the bottom and sides
of the bowl (by deepening the bowl) allows the user to accelerate the spoon more rapidly in a direction
perpendicular to the applied field without spillage. This modification of the bowl (as well as a
change in bowl/handle relationship, and often in the size of the bowl) can be
seen in a related specialised tool, the ladle.

Method of Use

The stuff to be transported is introduced into the bowl of
the spoon using different methods depending on its physical state. Liquid stuff
is usually put in the bowl by keeping the bowl horizontal, and moving it down
into the body of the liquid until the surface of the stuff is above the outer
rim (the lip) of the bowl. (The bowl referred to here and throughout this Entry
is the bowl of the spoon, not the vessel used to hold the liquid). At this
point, the liquid will flow into the bowl down the resulting gravitational
potential gradient, displacing the air from the bowl as it does so. When full,
the spoon is lifted out of the liquid. The liquid cannot flow out of the bowl,
due to the gravitational potential well imposed by its
shape.¹ Some liquid may be lost on the way to the
user's mouth, but this is usually only a small proportion of the content of the
bowl.

Solid stuff is usually introduced into the bowl by rotating
the spoon along its long axis, lowering one side of the bowl. This reduces the
gravitational potential gradient and physical barrer presented by the side of the bowl which prevents stuff from easily entering it. Deft manipulation of the spoon, sometimes in conjunction with the use of
another implement or a piece of bread can then bring the stuff inside the lip
of the bowl, and returning the spoon to an axially horizontal orientation traps
the stuff in the bowl.

Spoons can carry liquid stuff to a volume equal to the
volume of the interior of the bowl, plus any remaining stuff that adheres to
the external surface of the bowl. Spoons can carry more solid stuff, as the
structure of solid stuff prevents stuff protruding above the lip flowing out of
the bowl. Granular or powdery solid stuff are intermediate cases, as they can
flow under gravity or under the influence of acceleration.

Once at the mouth, the spoon is usually emptied in one of
two ways:

The slurp - this is most affective for liquid stuff. The
lips of the mouth are opened slightly and the bowl of the spoon, still held
horizontally, is brought up very close to or touching the lower lip at the gap
between the middle of the lips. The user then inhales rapidly. The pressure
drop caused by the movement of the air (the Bernoulli effect) causes the stuff
to flow upwards into the air stream and enter the mouth, where it is caught
when it bangs into the tongue. This is usually accompanied by a rotation of the
spoon along its long axis, towards the mouth, introducing more stuff into the
air stream. The bowl is often introduced into the mouth at the end of this
procedure to remove any remaining stuff. The slurp is particularly useful if
the bowl contains hot liquid stuff, as the creation of fine droplets of stuff
in the moving air tends to make it loose its heat very rapidly to the relatively
large volume of air, preventing burning of the mouth.

The placing the bowl of the spoon in the mouth - The lips
are closed around the bowl and used to retain its content in the mouth when the
bowl is removed.

Spoons vary in their shape and capacity depending on their
intended use. They are generally low maintenance tools, having no internal
moving parts. New materials continue to extend the possibilities of spoon
design. The story of the spoon is not over yet. Oh no.