An example of a early alarm.

Alarm

An example of a early alarm.

A small bell inside of a glass sphere.

Bell in globe

A small bell inside of a glass sphere.

An illustration of a human ear.

Human Ear

An illustration of a human ear.

"Where to stand so that an echo may be heard relative to the source." -Comstock 1850

Echo

"Where to stand so that an echo may be heard relative to the source." -Comstock 1850

A hand holding a U-shaped tuning fork.

Hand with tuning fork

A hand holding a U-shaped tuning fork.

A pair of hands holding a tube and tuning fork over a resonator.

Hands with tuning fork and tube

A pair of hands holding a tube and tuning fork over a resonator.

The membranous labyrinth is lodged within the bony labyrinth and has the same general form; it is, however, considerably smaller and is partly separated from the bony walls by a quantity of fluid, the perilymph. In certain places, it is fixed to the walls of the cavity. The membranous labyrinth contains fluid, the endolymph, and on its walls the ramifications of the acoustic nerve are distributed. Within the osseous vestibule, the membranous labyrinth does not quite preserve the form of the bony cavity, but consists of two membranous sacs, the utricle, and the saccule. The membranous labyrinth is also the location for the receptor cells found in the inner ear.

Membranous Labyrinth

The membranous labyrinth is lodged within the bony labyrinth and has the same general form; it is, however,…

A musical instrument is an object constructed or used for the purpose of making the sounds of music. In principle, anything that produces sound can serve as a musical instrument. The history of musical instruments dates back to the beginnings of human culture. The academic study of musical instruments is called organology.

Musical Instrument

A musical instrument is an object constructed or used for the purpose of making the sounds of music.…

"Reflection of sound." -Comstock 1850

Reflection

"Reflection of sound." -Comstock 1850

"Hold a lamp reflector or other large concave mirror directly facing the sun, so as to bring the rays of light to a focus...At some point, W, between F and C, the center of curvature of the reflector, hang a loud-ticking watch, and hunt for the point, X, at which the ear can most distinctly hear the ticking. Moving the reflector will render the sound inaudible." -Avery 1895

Reflection of Sound Using a Reflector

"Hold a lamp reflector or other large concave mirror directly facing the sun, so as to bring the rays…

"In a circle, sound is reflected from every plane surface placed around it, and hence, if the sound is emitted from the centre of a circle, this centre will be the point at which the echo will be most distinct." -Comstock 1850

Sound Reflection in a Circle

"In a circle, sound is reflected from every plane surface placed around it, and hence, if the sound…

"Fill with carbon dioxide a large rubber toy balloon or other double-convex lens having easily flexible walls. Suspend a watch, and place yourself so that you can just hear its ticking. Have the gas-filled lens moved back and forth in the line between watch and and ear until the ticking is much more plainly heard. Use a glass funnel as an ear-trumpet." -Avery 1895

Sound Refraction

"Fill with carbon dioxide a large rubber toy balloon or other double-convex lens having easily flexible…

"How sound reverberates." -Comstock 1850

Reverberation

"How sound reverberates." -Comstock 1850

Ear on foreleg of locust

Sensory Organs of Insects

Ear on foreleg of locust

Ear found on the basal segment of grasshopper abdomen.

Sensory Organs of Insects

Ear found on the basal segment of grasshopper abdomen.

A siren is a loud noise maker. The original version would yield sounds under water, suggesting a link with the sirens of Greek mythology. Most modern ones are civil defense or "air raid" sirens, tornado sirens, or the sirens on emergency service vehicles such as ambulances, police cars and fire trucks. There are two general types, pneumatic and electronic.

Noise Making Siren

A siren is a loud noise maker. The original version would yield sounds under water, suggesting a link…

A sonometer is an apparatus by which the transverse vibrations of strings can be studied. It is also called the monocord because it often has only one string. On the box are two fixed bridges, near the ends, and at one end is a pulley. A string, often a steel wire, is fastened at one end, run over the bridges and the pulley, and attached to a weight holder hanging below the pulley. Weights can be added to the holder to produce tension in the wire, and a third, movable bridge, can be placed under it to change the length of the vibrating section of the string. A Sonometer demonstrates the relationship between the frequency of the sound produced by a plucked string, and the tension, length and mass per unit length of the string.

Sonometer

A sonometer is an apparatus by which the transverse vibrations of strings can be studied. It is also…

"Apparatus used that will show changes in the flame upon the glass sheet M, when sound is introduced into the tube at A." -Avery 1895

Flame Sonometer

"Apparatus used that will show changes in the flame upon the glass sheet M, when sound is introduced…

"Bow or pluck the string of a sonometer near its end, thus setting it in vibration as a hole. The string will have the appearance of a single spindle as shown, and will sound the lowest tone that it is capable of producing." -Avery 1895

Sound Wave, fundamental frequency

"Bow or pluck the string of a sonometer near its end, thus setting it in vibration as a hole. The string…

"Lightly touch the wire at its middle point with the tip of the finger or the beard of a quill; the wire will vibrate in halves." -Avery 1895

Sound Wave

"Lightly touch the wire at its middle point with the tip of the finger or the beard of a quill; the…

Sound making amoung animals serves to aid in frightening away enemies or in warnng companions of their approach, for recognition among mates and members of a band or species. It also aids in the attracting and wooing of mates, and the interchange of information. The annoying, high-pitched, whining sound mosquitoes make is caused by their wings rapidly beating hundred of times per second. This diagram shows the auditory hairs on the antennae of a mosquito.

Sound Making

Sound making amoung animals serves to aid in frightening away enemies or in warnng companions of their…

Edison invented and developed the carbon microphone used in all telephones along with the Bell receiver until the 1980s. After protracted patent litigation, in 1892 a federal court ruled that Edison and not Emile Berliner—was the inventor of the carbon microphone. The carbon microphone was also used in radio broadcasting and public address work through the 1920s.

Telephone Transmitter Carbon Microphone

Edison invented and developed the carbon microphone used in all telephones along with the Bell receiver…

This telephone uses magnets that converts sound into electrical signals to be transmitted over distances and then converts the signals back.

First uses of the Telephone

This telephone uses magnets that converts sound into electrical signals to be transmitted over distances…

An example of how to produce a tone. This illustration shows one end of a string fixed to a hook and suspending a weight from the other end. When you pluck the string it causes it to make a musical note, also known as a tone.

Tone

An example of how to produce a tone. This illustration shows one end of a string fixed to a hook and…

"A glass bell is fixed to stand, and beside it is a stand carrying a small ivory ball. This is so arranged that the ball shall just rest against the rim of the glass, Now let the violin bow be rubbed with a lump of rosin, and then drawn steadily over the edge of the glass. A clear musical note will be produced, but the vibrations of the glass will scarcely be perceptible to the eye." -New, 1891

Tone

"A glass bell is fixed to stand, and beside it is a stand carrying a small ivory ball. This is so arranged…

"If a light strip of steel is firmly gripped at one end in a vice and the other end plucked aside, it will, when let go, vibrate backwards and forwards as shown; and if the vibrations are sufficiently rapid, a musical note will be produced." -New, 1891

Tone

"If a light strip of steel is firmly gripped at one end in a vice and the other end plucked aside, it…

"Grasp one end of a straight spring made of hickory or steel in one end of a vise, as shown. Pluck the free end of the spring so as to produce a vibratory motion. If the spring is long enough, the vibrations may be seen. Lower the spring in the vise to shorten the vibrating part of the rod, and pluck it again. The vibrations are reduced in amplitude, and increased in rapidity. Continued shortening of the spring will render the vibrations invisible and audible; the are lost to the eye, but revealed to the ear." -Avery 1895

Sound due to Vibrations

"Grasp one end of a straight spring made of hickory or steel in one end of a vise, as shown. Pluck the…

An illustration of waves demonstrating different nodes.

Waves

An illustration of waves demonstrating different nodes.

An illustration of various sound waves.

Sound Waves

An illustration of various sound waves.

An illustration of various sound waves.

Sound Waves

An illustration of various sound waves.

"It is apparent that the auditor, in this case, must be placed in the centre from which the sound proceeds, to receive the greatest effect. But if the shape of the room be elliptical, the sound may be made in one part, and the echo will be heard in another part, because the ellipse has two points, called foci, at one of which, the sound being produced, it will be concentrated at the other." -Comstock 1850

Whispering Gallery

"It is apparent that the auditor, in this case, must be placed in the centre from which the sound proceeds,…