The times on a sundial and clock can be half an hour or more different even though both are correct. Sundials are not affected by changing the clocks. When clocks are put forward during the summer, reading a sundial stays the same—the position of the sun in the sky has not changed.
Testimonials My parents received the sundial and love it! Place the paperweight or stones on the very edges of the plate to hold it in place. Every hour check your sundial and the position of the shadow on your plate. If you started at 10 A. Each time you check the sundial, write the hour on the edge of the plate where the shadow falls. Why do think the shadow is moving? What does your sundial remind you of? After several hours of tracing your own shadow observe the positions of each tracing.
Did your shadow move during the day? What else changed about your shadow with each tracing? What do you think caused these changes? Build a Cooler. Get smart. Sign up for our email newsletter. Sign Up. Support science journalism. Knowledge awaits. See Subscription Options Already a subscriber? As standard time is. A novel sun dial in which such regulation can be made is illustrated on this page. This dial differs radically from the common type. Instead of showing the time of day by a shadow cast by the sun, it employs a spot of direct sunlight which' is brought to bear upon a hair line on a white screen.
The dial of the instrument is tilted according to the latitude, so that it wiII lie parallel to the plane of the celestial equator. The photograph shows the instrument set for the latitude of New York. The base must be oriented accur1tely, and the dial face tipped to the latitude of New York which is about 41 degrees , the upper angle being found by means of the graduated sector on which the dial face is supported.
The dial proper is divided into equal divisions to indicate the hours of the day, and opposite the 6 A. As the face of the dial is parallel with the celestial equator, its edge forms an arUfcial horizon, along which the sun apparently travels. By setting up your sundial correctly and completing a few simple calculations, you can synchronize your sundial to clock time and know the hour no matter where you are. Support wikiHow by unlocking this staff-researched answer. To read a sundial, first place the sundial on a flat surface in a sunny spot.
Then, look where the shadow cast by the gnomon falls on the sundial. The number the shadow lines up with is what time it is. If the shadow falls between two numbers, the time is somewhere between those two hours. Sundials typically only have 12 hours on them the 12 daylight hours since they can't be used at night.
To learn how to make your time even more exact or use a vertical sundial, read on! Did this summary help you? Yes No. Log in Social login does not work in incognito and private browsers. Please log in with your username or email to continue. No account yet? Create an account. Edit this Article. We use cookies to make wikiHow great. By using our site, you agree to our cookie policy. Cookie Settings. Learn why people trust wikiHow. Download Article Explore this Article parts.
Tips and Warnings. Related Articles. Article Summary. Part 1. Place your sundial on a flat, horizontal surface. Make sure your sundial will be in direct sunlight all day.
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