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Magic tricks can draw on dexterity, science, technique or even psychology. Here, we offer you the chance to travel back in time, to the beginning of the 20th century, and to reveal to you a few tricks of the period.

Magic tricks can draw on dexterity, science, technique or even psychology. Here, we offer you the chance to travel back in time, to the beginning of the 20th century, and to reveal to you a few tricks of the period.

These water droplets are not falling; they're actually stuck in place. What we're seeing is the effects of an acoustic levitator. The device was initially developed by NASA to simulate microgravity. Now it's being used by the pharmaceutical industry do develop better drugs.

Scientists recently recovered sound from an artifact that historians believe is the earliest surviving talking doll record. The artifact is a ring-shaped cylinder phonograph record made of solid metal, preserved by the National Park Service at Thomas Edison National Historical Park.

In order to be able to reproduce sound, you have to understand how it is produced, from its nature to the resulting acoustics and vibrations in the neighboring environment. The article further develops the mechanisms for generating noise as well as possible applications.

To discover Chladni pictures. Various modes of vibration on a mechanical surface.