home *** CD-ROM | disk | FTP | other *** search
- This is !SlideRule, version 1.01 (28 December 1995)
-
- Intro
- =====
- For those people who remember far enough back, before Sir Clive Sinclair
- developed his early calculators, people who had to multiply could use log
- tables, which made multiplication a little easier, once you knew what you
- were doing. A quicker way of multiplying, dividing, and other operations,
- was to use, a device called a sliderule. This essentially consisted of two
- rules, fitted in a sliding arrangement, that could be positioned to read off
- for instance the result of multiplying two numbers.
-
- The Program
- ============
- The icon bar icon is installed in the usual way, by double clicking on its'
- icon in the filer window. Clicking on this opens the sliderule windows. The
- lower one can be dragged to left or right with the mouse.
-
- Sliderules
- ==========
- To multiply numbers you have to place one end, (the 1) of the lower moving
- rule on one of the two numbers. Now look at the other number of the sum, and
- read off the corresponding number on the top, fixed rule. This will be the
- answer.
-
- Example
- =======
- Use the mouse to drag the lower rule until the number 1 near the left of the
- moving side, until it is next to the two on the upper rule. Now look at the
- two on the lower scale. It will be next to the four on the upper scale. You
- will have seen how the slide rule operator knows that 2 * 2 =4.!!!
-
- While the rule is also in position, you will see that 2*3 =6 , 2*4 =8 and
- 2*5 =10. However if you try your luck with 2* 6 you will run out of top
- ruler. To do this sum you will have to reposition the lower rule so that the
- 1 near the right hand of the lower scale is next to the 2 on the top scale.
- Now you can read off that 2* 6 =12.
-
- Accuracy
- =========
- Sliderules have never been particularly accurate. By their nature, they are
- more accurate for some sums than others. This slide rule emulation, is worse
- than most real slide rules, despite the fact that I spent some time in
- drawing out the ruler accurately. The fact that inaccuracies can be easily
- seen is annoying, but in any case, noone is going to use their arc, which
- has a perfectly usable calculator free, for multiplication. The program has
- been written partly to give me some insight into sliderules, and partly
- perhaps to amuse some other people.
-
- Copyright
- =========
- This program is Public Domain. It may be distributed or
- copied freely as long as no part of this software is used in any other
- program, whether commercial or public domain,without my prior written
- consent, though any files created by this software are not bound by this
- condition. This software may not be distributed for a profit, save that
- required to cover packaging and media costs..
-
- Copyright (©) is retained by the author, who may be contacted at the address
- beneath. No liability can be accepted by the author for any loss or damage
- arising from use or misuse of this software.
-
- Acknowledgements
- ================
- Thanks to Paul Hobbs for his very useful !EventShell System.
- Look at the file 'Credits' by double clicking on !SlideRule with <shift> held down and then double clicking on the file 'Credits'.
-
- -----------------------------------------------------------------------------
- Any improvements or bugs to !Journal, please report to :-
-
- Robert Seago.
-
- 40 Alton Park Road
- Clacton On Sea
- Essex.
-
- CO15 1ED
-