Talk:Slide rule

Contents

1 Obsolete or not? 2 The c in c log(x) 3 Size of rule pics 4 Photo overlapping TOC 5 Sci/eng calcs 6 Listing on Peer review 6.1 Peer review comments 7 E6B or E6-B or E-6B? 8 von Braun photo

Obsolete or not?

are slide rules completely obsolete? surely they'd be useful in places or situations where there is no electric power, or as a backup.

Solar-powered claculators generally fit the bill, and are now cheaper to get than (now antique and no longer made) slide rules. Some older engineers who owned slide rules and know how to use them do indeed use them as a (nostalgic) backup, but even that use is uncommon. They can be useful in education, though--I had a math teacher who hauled a bunch out to teach logarithms quite nicely. Also, as the article says, airline pilots are still required to have and understand specialized circular rules.

The c in c log(x)

This page doesn't explain the "c" in c log(x). Obviously a constant, but what determines its value?

Any value of c will do. It is the distance between the two index marks, so it's determined by the length of the wooden sticks that the slide rule is printed on. - Dominus

Size of rule pics

The instructional slide rule illustrations are great, but could they be reduced in size somehow, without destroying the instructional value? The present figures exceed the width of a web browser window even at high resolutions. --Wernher 00:00, 19 Apr 2004 (UTC)

I have now scaled down the pictures a little. They obviously can't be scaled down much further without the markings becoming undistinguishable from each other, but the present size at the very least should be more suitable than before. --Wernher 23:37, 26 Apr 2004 (UTC)

I drew the instructional pictures, and I could redraw them to a new width if desired. But (1) when you say "they exceed the width of a web browser window" you mean they exceed the width of your web browser window; regardless of how small I make them they might still exceed the width of someone's web browser window. So how would I decide how wide to make them? And (2), even if they do exceed the width of your web browser window, so what? I do not see what the problem is. Please explain. -- Dominus 10:14, 27 Apr 2004 (UTC)

What I meant was that, as I said in my first comment, even at high resolutions like with my own browser window (roughly 1000 pixels wide, of which perhaps 800 is available for articles after Wikipedias left margin is accounted for), the pictures exceeded the window width and thus necessitated sideways scrolling (the "so what"). This should answer your two questions. In principle, yes, one never knows how small a browser window anyone uses, but one may assume that few users today strive with less than 800×600 pixel displays (and with the falling prices on 15" LCD screens of 1024×768 resolution, and the related sharp price drop of CRTs, I suspect that even 800×600 will soon be a thing of the past including almost all budget installations). --Wernher 17:58, 27 Apr 2004 (UTC)

With IE and Opera at least, there is no problem with wide pictures: they do not make the text wider as well.--Patrick 10:49, 27 Apr 2004 (UTC)

Yes, a good thing, no problems with the text; but still I think one should try and avoid the need for sideways scrolling entailed by very wide pictures. --Wernher 17:58, 27 Apr 2004 (UTC)

Sorry, I still don't understand. Yes, having wide pictures means that you have to scroll to see the whole thing. But you shouldn't have to scroll to see the parts of the diagrams that are referred to by the article text, so I don't see why this matters. In my opinion, it's more important that the part of the slide rule that is disucssed in the text be clear and legible than it is for the other parts to be visible at all. If you like, I can chop the rightmost end off of each picture; then they will fit and you won't have to scroll. -- Dominus 15:40, 28 Apr 2004 (UTC)

I must say I had no intention of stirring up this matter into some kind of 'hot' discussion. The pictures as they stand now is perfectly all right, and with my infinitesimal changes they are also within the width of a much larger proportion of the reading public's browser windows. Not all readers, of course, but I dare say many more than before. So why spend more time on this? I have no problem seeing it from your/the general point of view, but I can't quite say I see any motivation for much further arguing about the matter as it stands. --Wernher 02:28, 29 Apr 2004 (UTC)

That is not responsive to my questions. Since you don't seem to have a good reason for your change, and since you dont seem to want to discuss it, I am going to put it back the way it was. Thanks for your other contributions to this article. -- Dominus 11:26, 29 Apr 2004 (UTC)

Well, if that's how you feel, how about your earlier suggestion of chopping off the rightmost non-essential/ instructional part of the pictures? I still feel there is some merit in trying to avoid sideways scrolling. And I have no problem discussing this -- in fact I very much want to do so, contrary to the impression you may have got from my comments. In that case I have not expressed myself clearly. As the discussion stands now, I almost feel some kind of hostility(?). --Wernher 21:36, 29 Apr 2004 (UTC)

Photo overlapping TOC

Hi, Wernher -- I reverted your change to the location of the first photo, because it wasn't rendering properly in Firefox -- the photo was coming out on top of the table of contents. Hope that's OK. Reading over your dialog with Dominus above, I agree with you that Dominus's figures were too wide. Although he's right in theory that scrolling to the right is not necessary in order to understand the figures, it looked ugly, and the reader would not necessarily realize when first going through the examples that scrolling was not needed. I've tried to solve the problem by replacing the figures with new ones representing single-decade scales rather than double-decade ones. This allows all the examples to fit within a comfortable width. --Bcrowell 04:54, 30 Apr 2005 (UTC)

Heh, this is interesting: the reason I changed the location of the uppermost photo in the first place was that it came up on top of the table of contents! :-) Strange. Or does it mean that my browser (no prize for guessing which one...) places the TOC on the left hand side by default while Ff does the opposite? Oh well. I think we might have a "double Murphy" here. BTW, thanks for fixing the other figs. --Wernher 05:14, 30 Apr 2005 (UTC)

Ugh -- what a pain! My browser also puts the TOC on the left, but the overlapping happens when I use "right" for justification, not when I use "none." So are you saying that in its current state, it overlaps for you? Its current state is "Image:pocket_slide_rule.jpg|frame|none|A slide rule being used to multiply by 2. Each number on the D scale is double the number above it on the C scale." In this state, it does not overlap for me. --Bcrowell 15:14, 30 Apr 2005 (UTC)

I've posted at the Wikipedia:Help desk to see if anyone knows how to fix this. --Bcrowell 17:13, 30 Apr 2005 (UTC)

I tried adding a fix suggested by the help desk. Wernher, can you tell me if it fixes it?--Bcrowell 15:06, 1 May 2005 (UTC)

Nope, the photo still appears above the TOC, leading to unnecessary waste of vertical display area IMO. :-( Hmm, perhaps the question then becomes: what is the most common browser as of this writing? Should one let that decide what code to use? Or, is that a despicable view, since it may depend on an error in the rendering engine in the dominant browser (how do we determine which browser is at fault, BTW?). --Wernher 00:54, 4 May 2005 (UTC)

Oh, I see -- you just don't want it above the TOC? You must have a wide screen -- on mine, there's no possible way for that wide figure to fit side by side with the TOC. I think it's right the way it is.--Bcrowell 04:14, 4 May 2005 (UTC)

Argh, now I understand---I misunderstood the term "on top of" to equal "above"... Now, what you have been telling me all along is that the photo actually overlaps the TOC like a "double exposure"? That I most certainly agree is a Bad Thing™. :-) You see, I was about to suggest the following:
"If the figure turns up above the TOC for you (and likewise for others with not-very-wide screens) no matter what we do with the WKP src code, why not use the <align=right> scheme anyway---so that everyone get what they want? :-) There's not any drawbacks with that, is there?"
But that is really not an option if I understand you correctly, then. Oh well. As the laywers say (on TV, at least): "I have nothing further"... Sincerely sorry for wasting (y)our time. --Wernher 11:25, 4 May 2005 (UTC)

Sci/eng calcs

The rationale behind my qualifying the word 'calculators' with 'scientific/engineering' in the intro paragraph is that slide rules were not essentially replaced by simple four-function calculators unable to compute trigonometric and logarithmic functions as well as roots. Only with the advent of scientific pocket calculators were slide rules definitely obsolete, although the price point of those calculators kept them out of reach for large parts of the potential user base until the latter half (the end, really) of the 1970s. --Wernher 11:48, 17 Aug 2004 (UTC)

Listing on Peer review

This article has been listed on WP:PR to gain wider commentary. Please see the comments there and try to help collaborate in improving this article. Thanks - Taxman 22:41, Aug 23, 2004 (UTC)

These are the comments from WP:PR; this article has now been removed from that page due to inactivity. Alanyst 17:40, 18 Sep 2004 (UTC)

Peer review comments

Thinking of nominating this for featured status. Anyone interested in helping? Seems to be a very good start. Alanyst 02:52, 15 Aug 2004 (UTC)

• The opening sentence seems a bit odd- it defines the slide rule solely by contrasting it with an instrument that replaced it. How about someting saying what the slide rule is, not what it isn't? Markalexander100 05:56, 15 Aug 2004 (UTC)
  • Good suggestion. I have revised the intro. Anything else? Alanyst 15:00, 17 Aug 2004 (UTC)
• Good article. I like it. A few notes: The history section needs to be expanded. When were they first used or developed, and what were the precursors? Also the section on standard linear rules says 2 or 3 significant figures of precision are possible, but I thought with custom, longer units, higher precision was possible? I remember looking at the Guiness record for the longest slide rule. In addition a picture of a circular slide rule would be very good to show the contrast. I had never reallized there were circular slide rules. Mention of the cultural impact of slide rules being so widespread and then replaced so that current students only learn about them as a history lesson might be appropriate. I think the slide rule is the MIT or MIT math club symbol too. - Taxman 20:39, Aug 19, 2004 (UTC)
• I'd like to point out that the scales in the figures don't look quite right; some numbers seem to be positioned linearly instead of logarithmically. For example, 4.5 is shown midway between 4 and 5; that physical location should correspond to (approximately) 4.3. --Coneslayer 21:46, 2005 Mar 10 (UTC)
  • Never mind, I was thinking wrong. --Coneslayer
    • You were thinking more or less correctly---the 4.5 mark should not in fact appear midway between 4 and 5. The distance between the 4 and 5 marks is log(5) - log(4) = 0.223, and the distance between the 4 and 4.5 marks is log(4.5) - log(4) = 0.118, so the 4.5 mark appears 0.118/0.223 of the way from the 4 to the 5, or about 53%. Careful inspection of the diagram will reveal that it is indeed slightly more than halfway over. I very much appreciate that you took the time and touble to examine the diagram so carefully. Thanks! -- Dominus 14:49, 11 Mar 2005 (UTC)

E6B or E6-B or E-6B?

The "E-6B" name variation used in the article was never introduced to me by any of my flight instructors. They used E6B or E6-B. However, a google test says that all of the spellings are widely used: E6B - around 20,000 E6-B - slightly over 10,000 E-6B - (the one used in the article) - the least popular, albeit just about 10% less than E6-B

Change to E6B? BACbKA 10:21, 27 Sep 2004 (UTC)

I just created a new article on the E6B for Wiki; very very rough outline, but it's there. I'm using 'E6B', and just edited this page to use that format. I've even see people use all three spellings in the SAME paragraph elsewhere. Comments & help with the new E6B article welcome! --Madpilot 02:16, 13 Mar 2005 (UTC)

von Braun photo

I would like to have some comments on the photo of von Braun which is used in the article about him -- I wonder if that is one of his slide rules being partly visible in the picture. Please comment at the photo's talk page. --Wernher 15:39, 10 Dec 2004 (UTC)