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Member Products:17-inch Galileo Thermometer

17-inch Galileo Thermometer

$55.00

Price: $55.00

Item#:1075151

Qty: Available, ready to ship.





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Art meets science in this colorful glass thermometer. In 1593, Italian physicist Galileo invented a thermometer based on the principles of relative density. Individually calibrated weights containing a mixture of ethanol and dye float in a sealed tube with de-aromatic oil where they rise and fall with the temperature and the resulting changes in liquid density.


Displays temperatures in Fahrenheit in 2° increments from 68° to 80°. Accurate to within 2°. 17"H.

In the 2nd century B.C., Greek scholar Archimedes discovered the law that states any object in a fluid displaces its own weight of fluid. He went a step further when he described the principle of buoyancy—that if an object is more dense than an equal volume of water, it sinks; if it's less dense, it floats. A simplified way of understanding density in this example is that it's the relative "heaviness" of objects of the same volume—a marshmallow is less dense than a marble of the same size and shape.


Almost 2,000 years later, Italian scientist Galileo discovered that a liquid's density is affected by changes in temperature. As temperatures rise, a liquid's density decreases. This means that objects that float in room temperature water would sink as the water is heated. He applied his discovery to create what is now known as a Galileo thermometer.


In a Galileo thermometer, sealed glass bubbles filled with a mixture of ethanol and dye have weights attached that are marked with different degrees Fahrenheit. The bubbles are suspended in a tube of de-aromatic oil. The weights give the bubbles different densities from each other and from the liquid in the tube.


When the atmospheric temperature rises, the density of liquid in the tube decreases, which changes the relative density of the glass bubbles. So, as the temperature increases, the liquid's density decreases, which means more bubbles will sink because they are now more dense than the surrounding liquid. At the highest temperatures, the lightest (least dense) bubble will finally sink. When temperatures drop, the opposite happens and more bubbles rise.


To read a Galileo thermometer, look at the lowest hanging bubble in the middle of the tube—the one that is not entirely sunk, nor entirely floating at the top. This bubble is in equilibrium with the surrounding liquid, and its tag will tell the current temperature.


REVIEW SNAPSHOT®

by PowerReviews
17-inch Galileo Thermometer
 
4.2

(based on 16 reviews)

Ratings Distribution

  • 5 Stars

     

    (10)

  • 4 Stars

     

    (3)

  • 3 Stars

     

    (1)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (2)

81%

of respondents would recommend this to a friend.

Most Liked Positive Review

 

Galileo Thermometer

I have a Galileo at home, got it from a yard sale, did'nt know what it was until I saw it in NG order catalog,I just liked it so I got it....Read complete review

I have a Galileo at home, got it from a yard sale, did'nt know what it was until I saw it in NG order catalog,I just liked it so I got it. It really works, I tryed it tonight in my home.I can't find anything wrong with it.

VS

Most Liked Negative Review

 

Galileo Disappointment

My thermometer arrived with a broken ball inside. I was very disappointed and called right away as it was to be a Christmas gift for my Dad. They acted like this was a common...Read complete review

My thermometer arrived with a broken ball inside. I was very disappointed and called right away as it was to be a Christmas gift for my Dad. They acted like this was a common thing for these to arrive broken (how could they NOT? They are ALL GLASS and full of LIQUID!) and said that another would be shipped right out. In all the busy-ness of the holiday I had to get my dad another gift because the replacement never arrived. I just called yesterday because I noticed my credit card was never refunded for the shipping, only the item itself. I was told these are on backorder till 1/15/12. That would have been nice to have known. I told them to cancel the order :-( Too bad, too...because I know someone who has one of these thermometers and it is the coolest! I'd recommend buying one at a store if at all possible. Too risky to order such a fragile item from a catalog.

Reviewed by 16 customers

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4.0

A piece of galileo in your home!

By Fullmoonwalker

from New Rochelle, NY

Verified Buyer

Pros

    Cons

      Best Uses

        Comments about 17-inch Galileo Thermometer:

        Useful within the home but not outside due to limited temperature range.
        Still, a satisfying, marvelous inventive way of gauging the temperature

        • Was this a gift?:
        • Yes

        (1 of 1 customers found this review helpful)

         
        5.0

        This is fascinating!

        By Bubbe

        from Surprise, AZ

        Verified Buyer

        Pros

        • Is Fun To Watch Balloons

        Cons

        • none

        Best Uses

        • For Decor And Temp

        Comments about 17-inch Galileo Thermometer:

        It is fairly accurate and is a decorative piece of science from the past. It is fun to watch the balloons change with the temperature.

        • Was this a gift?:
        • No

        (0 of 2 customers found this review helpful)

         
        1.0

        pack it properly

        By Paul the horse man

        from Ohio

        Verified Buyer

        Comments about 17-inch Galileo Thermometer:

        first thermometer came with broken degree bulb inside of tube so it did not work - sent it back

        second thermometer came completing broken, oil everywhere UPS put it in black garbage bag and left on steps.

        Need to learn how to safely package this thermometer for shipping!!!

        (1 of 1 customers found this review helpful)

         
        5.0

        The Super, Intriguing Un-thermometer!

        By Dano the Mano

        from Toronto, Ontario, Canada

        Verified Buyer

        Pros

        • Conversation piece
        • Fascinating for Kids
        • Quality construction
        • Visually Intriguing

        Cons

        • No Celcius
        • Only Fahrenheit

        Best Uses

          Comments about 17-inch Galileo Thermometer:

          A Great Gift, but you'll want to keep it for yourself. Even the beautifully shaped, quality, glass cylinder and floating glass bulbs are a beautiful site that will put you in a trance. Enjoy!

           
          5.0

          Unique gifts

          By Shambles

          from Tuscaloosa, AL

          Verified Buyer

          Comments about 17-inch Galileo Thermometer:

          This was a gift to my sister. It was shipped to her, so I didn't actually see it but she and her husband have it proudly displayed in their beautiful kitchen! I wish it had been available gift wrapped, but that's not really important.

          It's the second (but not the last) gift I've purchased from the NatGeo store. Great stuff!

          (1 of 2 customers found this review helpful)

           
          3.0

          The Temperature range must be checked ag

          By Chao

          from Petaling Jaya, Malaysia

          Comments about 17-inch Galileo Thermometer:

          NG should be indicated the temperature range. from 68 F to 80 F which is equivalent to 20 to 26.7 C.
          Malaysia's temperature is about 36 C daytime and 27 C at night.
          Hence I have to turn on my air-conditioner to see how it works. I'm rather disappointed!

          (1 of 1 customers found this review helpful)

           
          4.0

          GALILEO THERMOMETER

          By PADDLES

          from SYDNEY AUSTRALIA

          Verified Buyer

          Pros

          • Attractive functional
          • Conversational
          • FAIRLY UNIQUE

          Cons

          • POSSIBLY PRECARIOUS
          • TRANSLATES TO FAHRENHEIT
          • WE LIVE IN A CENTIGRADE

          Best Uses

          • decoration
          • RELATIVE MEASURE

          Comments about 17-inch Galileo Thermometer:

          DECORATION AND AMUSEMENT FOR MY WIFE WHO CONSTANTLY CHECKS IT DURING THE DAY FOR CONDITIONS PROGRESS.
          IT ATTRACTS COMMENT AND PROMOTES CONVERSATION.
          IT APPEARS TO BE FRAGILE SO A COMPROMISE LOCAL IS REQUIRED
          I AM AN ENGINEER AND THE FACT THAT IT IS CALIBRATED IN FAHRENHEIT ANNOYS ME.
          THE RANGE OF TEMPERATURES IS LESS THAN THAT OF OUR AREA.

           
          5.0

          Great Visual Center Piece.

          By Lee

          from Round Rock, Texas

          Verified Buyer

          Pros

          • Works Great

          Cons

            Best Uses

            • Display piece

            Comments about 17-inch Galileo Thermometer:

            Arrived intact and it looks and works great.

            (0 of 1 customers found this review helpful)

             
            5.0

            Delighted!

            By Doting Grandmother

            from Dallas, TX

            Verified Buyer

            Comments about 17-inch Galileo Thermometer:

            I bought this as a gift for my 14-year-old grandson. We both "checked it out" and found it to be very accurate. It's colorful and fun to look at as well. A great gift!

            (1 of 1 customers found this review helpful)

             
            5.0

            Yeaaa Galileo!

            By deeber

            from Florida

            Verified Buyer

            Pros

            • This made a lovely gift

            Cons

              Best Uses

                Comments about 17-inch Galileo Thermometer:

                It works so well, is practical and a work of art. Hopefully NG will make the next larger size available in their catalog, as it has more floaters and will give an even wider range of temperatures.

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