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, eg 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 shape¹. 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 barrier 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. 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 effective 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 of 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.