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An hourglass is a mechanical device used to measure the passage of time. It comprises two glass bulbs connected vertically by a narrow neck that allows a regulated trickle of material from the upper bulb to the lower one. Factors affecting the time interval measured include the sand quantity, the sand coarseness, the bulb size, and the neck width. Hourglasses may be reused indefinitely by inverting the bulbs once the upper bulb is empty.

Hourglass in a three-legged stand

An hourglass (or sandglass, sand timer, sand watch, or sand clock) is a mechanical device used to measure the passage of time. It comprises two glass bulbs connected vertically by a narrow neck that allows a regulated trickle of material (historically sand) from the upper bulb to the lower one. Factors affecting the time interval measured include the sand quantity, the sand coarseness, the bulb size, and the neck width. Hourglasses may be reused indefinitely by inverting the bulbs once the upper bulb is empty.

Set It Off - Hourglass (Official Music Video)

Set It Off - Hourglass From the album 'Midnight' - out now Apple Music: http://found.ee/midnightam iTunes: http://found.ee/midnight Spotify: ...

Set It Off - Hourglass

Set It Off - Hourglass From the album 'Midnight' - out now Apple Music: http://found.ee/midnightam iTunes: http://found.ee/midnight Spotify: ...

5 BEST HOURGLASS MAKEUP Products! | Jamie Paige

Today i'm talking about 5 makeup products from Hourglass cosmetics that are worth checking out! ___ Products mentioned: - Hourglass Caution Mascara ...

Full Face Using HOURGLASS COSMETICS #FFF

THANKS FOR WATCHING FAM LOVE U ❤️ #FFF #HOURGLASSCOSMETICS --------------------------------------------------------------------------------------------- COME ...

Disclosure - Hourglass ft. LION BABE

'Hourglass' taken from the new album 'Caracal'. 'Caracal' the new album is out now https://disclosure.lnk.to/CaracalAlbumDeluxeID Follow Disclosure ...

how to get an hourglass figure in 3 days ft. body transformation

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