Toggle navigation. User Contributions:. Comment about this article, ask questions, or add new information about this topic: Name:. E-mail: Show my email publicly. Human Verification:. Public Comment: characters. Send comment. Other articles you might like:. Schickard was born on April 22, , at Herrenberg, Wiirttemberg.
He was educated for the church, and at an early age became known for his knowledge of Hebrew. At the age of twenty-seven years he was appointed to the chair of Hebrew at Tubingen, and in was made professor of astronomy.
He was also an inspector of schools at Stuttgart. In some of his least-known books are to be found early observations on the aurora, an account of the comet of which caused considerable commotion on its appearance, and his views on the refraction of light and the theory of the rainbow. But Apollo, acquainted with his knavish tricks from his infancy, would not allow him to pass altogether unnoticed. To be brief, I have been more fortunate than those hunters after Mercury who have sought the cunning god in the sun.
I found him out, and saw him, where no one else had hitherto seen him. Reprints and Permissions. You would burst out laughing if you were present to see how it carries by itself from one column of tens to the next or borrows from them during subtraction. Kepler must have written back asking for a copy of the machine for himself because, on February 25, , Schickard again wrote to Kepler giving a careful description of the use of the machine, together with several drawings showing its construction.
He also told Kepler that a second machine, which was being made for his use, had been accidentally destroyed when a fire leveled the house of a workman Schickard had hired to do the final construction.
These two letters, both of which were found in Kepler's papers, give evidence that Schickard actually constructed such a machine. However, the drawings of the machine had been lost and no one had the slightest idea of what the machine looked like or how it performed its arithmetic. Then some scholars who were attempting to put together a complete collection of Kepler's works were led to investigate the library of the Pulkovo Observatory near Leningrad.
While searching through a copy of Kepler's Rudolphine Tables, they found a slip of paper which had seemingly been used as a bookmark. It was this slip of paper which contained Schickard's original drawings of the machine.
Little detail can be seen, but with the hints given in the letters it became possible to reconstruct the machine. The baron was able to figure out the details of the machine because, among other things, he is an expert on the techniques used by seventeenth-century clockmakers. This reconstruction was featured on a stamp issued by West Germany in to honor the th year of its invention.
In the stamp illustration, the upper part of the machine is set to show the number being multiplied by 4.
The result of this multiplication would be added to the accumulator, using the lower portion of the machine. The upper part is simply a set of Napier's "bones" multiplication tables drawn on cylinders in such a way that any particular "bone" may be selected by turning the small dials in Schickard's drawing. Moving the horizontal slides would expose different sections of the "bones" to show any single-digit multiple of the selected number; the fourth multiple is shown exposed in the stamp illustration.
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