The Unisys History Newsletter is written and published by George Gray. George is a Systems Programmer for the State of Georgia Department of Administrative Services and is heavily involved in Unite Inc., a Unisys User Group. He began his work on the Unisys History Newsletter as a hobby and privately published his first six newsletters. Then, he began writing a regular computer history column in UniSphere magazine.
Twenty years may be long enough to justify a few personal reminiscences. They begin during a chamber music performance in the Cornell Student Center when I first came to think about the promise of gamma-ray astronomy.
In the early 1850's there was a rush of designs for a new stethoscope that used both ears. This new 'Bi-aural' or 'Binaural' instrument was felt to be the future of auscultation. Interestingly enough, the idea for a binaural stethoscope was first introduced in 1829, just a few years after Laennec's original instrument.
As a small boy, scientists, jet pilots, and Captain Midnight were my heros; airplanes, rocket sleds, atoms and astronomy were some of my amazements. I had a nice collection of model planes and rockets. I loved the rockets aerodynamic shapes and the pictures of their fiery takeoffs. Of course I had no idea of the weapon their full-sized counterpart had been designed to carry nor anything of its power.
In February 1996 Ancient Medicine/Medicina Antiqua went on line. In designing the site, I hoped to produce a reliable source for peer-reviewed information about the medicine and medical thought of the Greeks and Romans from Mycenaean times to the fall of the Roman Empire. By early 2003 the site had grown, won over a dozen awards, and become one of the Internet's major resources in its field
With its numerous cultivated varieties, the sweet orange (Citrus sinensis Osbeck) constitutes one of the world's most popular and recognizable fruit crops. Sweet oranges are citrus fruits (Citrus spp.), which are regarded as high sources of vitamin C (ascorbic acid) and other fruit acids. These fruits are hesperidiums, because of their fleshiness and separable rind. Physically, citrus fruits consist of forty to fifty percent juice, twenty to forty percent rind and twenty to thirty-five percent pulp and seeds. Chemically, they contain eighty-six to ninety-two percent water, five to eight percent sugars and one to two percent pectin with lesser amounts of acids, protein, essential oils and minerals (Janick et. al. 1981). Citrus fruits grow on small evergreen trees, many of which depend on root mycorrhizae (Janick et. al. 1981). Most of these C3 plants are cultivated as scions on rootstocks. All Citrus species have a diploid chromosome number of eighteen and are interfertile.
Apart from the Vikings, who without doubt navigated and kept track of time by means of the stars, the first important Danish astronomer was Peder Nightingale. In 1274 he observed the sunlatitude from Roskilde where he was a canon, and based on these observations he made tables showing the length of day and nights. Later he published a widespread calender in Paris. There is some indication in the sources, that he didn't believe in the relation between astrology and astronomy which was the common belief at that time.
In 1417 were "Speculum Planetarum" published by Johannes Simones de Selandia a book about the movements of the planets, very little is known of Johannes.
Although certainly not the first trigonometric table, Ptolemy's On the Size of Chords Inscribed in a Circle (2nd Century AD) is by far the most famous. Based largely on an earlier work by Hipparchus (ca. 140 BC) it was included in Ptolemy's definitive Syntaxis Mathematica, better known by its Arabic name Almagest. In this paper I will describe the geometric theorems used in the construction of this table and attempt to relate them to their contemporary trigonometric counterparts.
In 1998 we celebrate Simon Stevin's 450-th birthday. In the low countries he is not only remarkable for his contributions to mathematics, physics and many other fields of knowledge, but also for his influence on the Dutch language. Like his contemporary Galilei he preferred to publish his findings in his native language and he coined new Dutch terms when necessary, many of which are still in use today.
