Pursuit-Core-Web-HTML-Introduction-Lab/sundial.html at bd8f71b4e2f5a45dabfbe10bc621bec3fe71e0cb · joinpursuit/Pursuit-Core-Web-HTML-Introduction-Lab · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <h1> Sundial </h1>
    <p> From Wikipedia, the <em>free</em> encyclopedia.</p>

    <p> <strong> sundial measures time by the position of the sun</strong>. The most commonly seen designs, such as the
        'ordinary' or standard garden sundial, cast a shadow on a flat surface marked with the hours of
        the day. As the position of the sun changes, the time indicated by the shadow changes. However,
        sundials can be designed for any surface where a fixed object casts a predictable shadow.

        Most sundial designs indicate apparent solar time. Minor design variations can measure standard and daylight saving time, as well.</p>
<h2>History</h2>
<p> Sundials in the form of obelisks (3500 BC) and shadow clocks (1500 BC) are <strong>known from ancient Egypt</strong>, and were developed further by other cultures, including the Chinese, Greek, and Roman
    cultures. A type of sundial without gnomon is described in the old Old Testament
    (Isaiah 38:2).

    The mathematician and astronomer Theodosius of Bithynia (ca. 160 BC-ca. 100 BC) is said to have
    invented a universal sundial that could be used anywhere on Earth. The French astronomer Oronce Fine constructed a sundial of ivory in 1524. The Italian astronomer Giovanni Padovani published a treatise on the sundial in 1570, in which he included instructions for the manufacture and laying out of mural (vertical) and horizontal sundials. Giuseppe Biancani's Construction instrumenti ad horologia solaria discusses how to make a perfect sundial, with accompanying illustrations.</p>
<h2>Installation of standard sundials</h2>
<p> Many ornamental sundials are designed to be used at 45 degrees north. By tilting such a sundial, it may be installed so that it will keep time. However, some mass-produced garden sundials are inaccurate because of poor design and cannot be corrected.</p>
</body>
</html>