change of email address
Please note that my new email address is da...@davidbrownsundials.com. I have tried to contact the uni-koeln address manager, but to no effect, to transfer my 'account' but to no effect. how do I do it? David Brown Somerton, Somerset, UK AOL Email goes Mobile! You can now read your AOL Emails whilst on the move. Sign up for a free AOL Email account with unlimited storage today. --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: 3D analemma
Silas Higgon of BSS includes tham on some of his armillary spheres. He may know details of construction. David Brown Somerton, Somerset UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Translucence
In general, marble is not favoured for exterior stone work in UK - pollution and all that, not to mention algae etc. Surprisingly, black/dark slate with a matt finsih gives a very good surface for shadows. David Brown Somerton, Somerset, UK -Original Message- From: Roger Bailey To: sundial@uni-koeln.de Sent: Wed, 18 Mar 2009 3:43 am Subject: Translucence You may think, as?I did, that white marble is an ideal base material?for a sundial. The rock is relatively easy to engrave; the white surface should provide good contrast for the shadow. ? This is not necessarily so. I found from tests with a prototype that the translucence of marble, that wonderful milky quality so favoured by sculptors, does not show high contrast shadows. The light from the bright areas seems to diffuse to the shaded zone and the shadow contrast can be greatly reduced. The effect is similar to the shadow formed on a hazy day when thin clouds diffuse the sunlight. ? My prototype was a marble tile, 30 cm square, 1 cm thick. I could see the outline of my hand through the rock. One side was polished and glossy, the other a rough matte finish. The glossy surface of the translucent material did not show high contrast shadows even in bright sunlight. The matte finish was significantly better but still the contrast was lower that the shadow of a white piece of paper. The prototype was a sunset sundial and the shadows approaching sunset tend to be diffused. The translucent base made them invisible. ? This experiment reminded me of a previous experience with stainless steel. Again the shadow contrast on the shiny surface was poor. Shiny and translucent? Both are bad for shadow contrast. ? Regards, ? Roger Bailey www.walkingshadow.info --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Experimental Method for Earth Radius
Has anyone worked out a value for this acceleration, and timings involved in start-to finish of the terminator tack up a building of presumed height? David Brown Somerton, Somerset, UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Earliest UK sundial?
Can anyone tell me which is thought to be the earliest UK sundial? David Brown Somerton, Somerset, UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Sundial time marks in France.
I must be getting old... I'm doing a design for an analemmatic dial in France. France is in the GMT time zone but chooses to be +1 on GMT in the winter months and +2 in the summer months (daylight saving). I have the co-ordinates etc for the dial's lat and long - no problem here. Am I right in labelling the hour points as follows, for showing winter months... The hour point nearest to the meridian line (which would have been 12 in UK) will be 1 pm in France. If the dial is to indicate daylight saving hours, then the point nearest top the meridian will be labelled 2pm. Best wishes to all in these sun-less days David Brown Somerton, Somerset, UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Latin mottoes
Dear John and all the rest Herewith some translations kindly supplied to me by my former classics teacher, Michael Bishop, now in his 80's but who thoroughly enjoys a puzzle or three. 1) OMNIA FERT AETAS SECUM, AUFERT OMNIA SECUM [I suspect the comma should follow the first 'secum']; lit: time/ brings/ all things/ with itself, takes away/ all things/ with itself . sc.: Time brings everything in its train, and with its train sweeps everything away. 2) MINUTA SUNT QUAE SPECTAS, NON QUAE PERDIS: lit: minutes are what you look at, not what you lose. sc: think of the passing moments as gifts experienced rather than fleeting things lost. [This reminds me of the derivation of 'minute' from 'minuere', to divide up: the ' hora minuta' being the hour divided into sixty, the 'second' being the 'hora minuta secunda' (from 'sequi', to follow), the subsequent division of the already divided hour. It also reminds me of the mynah birds in Aldous Huxley's utopian 'Island', trained to sing 'Here and now, boys!'] 3) TENERE NON POTES [the shortest and hardest!) Lit: you can't keep hold. sc.viz [I suppose]: Time doesn't stand still - i.e tempus fugit (flees, eludes you ,rather than 'flies'). What deep philosophical musings sundials arouse! David Brown, Somerton, Somerset, UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Richard Schmoyer's orginal manual in WORD format
Thanks, Bill. Good stuff. David Brown Somerton, Somerset, UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Blisters on a slate sundial
The Stone Federation GB may have the answer _www.stone-federationgb.org.uk_ (http://www.stone-federationgb.org.uk) Let us know how you get on. David Brown Somerset UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: How to engrave marble?
The cost of a tungsten-carbide-tipped lettering chisel is about £15, and of a suitable dummy about £25. Not much cost, but quite a bit of skill needed. David Brown Somerton, Somerset UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Shepherd's (cylinder) dial.
I recently acquired a modern reproduction shepherd's dial. On it is an inscription in latin: Quaere diem anni eique respondentem locum solis cui applicandus superne stylus competens longior, sole existente in signis borealibus brevior in austrinis: et umbra , rectis parallela, extremitate sua indicabit horam diei. I have had some help with translation, which has been given as: Find the day of the year and the position of the sun corresponding to it. To it is to be applied, on top, the appropriate gnomon the longer one when the sun is in northerly signs the shorter in the southerly ones and the shadow, parallel to the verticals, at its extremity will show the hour of the day. My questions are these: 1. Is this a sufficiently accurate translation? 2. I am puzzled by the 'longer ' and 'shorter' gnomons (they are provided in the inside of the hollow cylinder and either can be fixed in place easily). I reckon that the longer one should be used whern the sun is in the northern signs(= northerly declination) rather than the longer one. Am I right? 3. The dial is made for Madrid's latitude (40.4 deg N). What physical correction should I make for correct time-telling in, say 50.4 deg N.? Tilting comes to mind (10 deg inclination in the meridian?) as for horizontal dial latitude corrections. David Brown Somerset, UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Scratch dials - Ethelbert Horne.
In 1917 Dom Ethelbert Horne did a survey of scratch dials ('Primitive
Sundials or Scratch Dials') in Somerset and published a book on his findings..
I
understand (from my 1929, second edition) that that the second half of that
first edition consisted of a list of all the Somerset churches having Scratch
dials on them. Is there any reference to there being any Scratch dials on the
Bath Abbey Church of Saints Peter and Paul, and if so, how many were there,
where were they, and are there any pictures of them? Mrs Gatty (rather
earlier) says (p.72) that "on the walls of Bath Abbey Church there are no less
than
thirteen dials, varying in size, and the number of lines, and three of these
are on the north side".
I'd be very glad to have any information that anyone can supply on these
dials, none of which is visible today.
David Brown
Somerton,
Somerset
---
https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Help Oscar!
Just to correct some wrong information..There was a book for schools written through the auspices of the Bristish Sundial Society by a group of members of which I was only one of nine on the team. It was called "Make a Sundial", and brought out in 1991 in response to many queries sent to BSS by schools asking for help with topics in the National Curriculum. It sold very well and went into a second edition in 1993, and was also translated into Dutch. In 2003 Jane Walker (the guiding light of the original team) revised the book, keeping the same title, and it is currently for sale through BSS. Its ISDBN is 0 951 8404 5 2. David Brown Somerton, Somerset, UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Could anyone please translate this Latin inscription, for me ?
The moving sun shines on you, unmoving. It refers to a stationary gnomon while the moving sun casts the shadow. I used an inscription simil;ar to this on an anelemmatic dial some years ago. David Brown Somerton UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Seeking advice, on starting a 'sundial business'
Dear Keith, Just a few tips.. Painted sundials on playgrounds are quick and easy, but they need to have the markings repainted at fairly frequent intervals. You'll need to have studs hammered into the playground to give you the reference points for each repainting. Dials set into grass are great provided that you have someone who is prepared to trim round the components. I did one some time ago wityh the hour points as numerals cut into bricks of reconstituted stone. The worms were pretty good at getting the bricks to sink in about 2 years well below their original levels. Have fun. David Brown Somerton, Somerset, UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Paint on stainless steel plaques
I am soon to commission the making of a brushed stainless steel equation of time plaque to go with a sundial. Experience of two plaques in recent years tell me that the black paint (or whatever) used to in-fill the etchings does not last more than a couple of years or so. Has anyone got a recipe for an improved paint, or an alternative way of guaranteeing permanent contrast between etching and background surface? David Brown Somerton, Somerset, UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: thank you, Daniel!
I'll second that. David Brown www.DavidBrownSundials.com Somerton, Somerset. UK --
Vertical Bullnose dial
Is there a simple solution to this problem? Two meeting vertical walls each decline 5 degrees away from south. The meeting surface is a curve of radius about 2 metres. There is thus a vertical cylindrical curved surface whose centre line faces south. The curved surface is about 1 metre wide. This is the 'bullnose'. It is proposed to put a sundial centrally on this wall with the gnomon on the centre line. Would it make any sense at all to have a linear gnomon, since the hour lines will be curved until they reach the plane part of the walls, or am I bound to have to use a nodus only as the indicator of time? How do I work out the geometry of the dial, taking account also of the seasons? I would prefer to have a calculated geometry rather than one derived from a trigon. I suppose that one way to draw out the dial would be to start with a delineated vertical dial and by geometrical 'constructions' project it on to the vertical wall taking account of the solar declination for each line of projection. Help There is to be an equation of time curve on a nearby plaque with longitude correction applied. Any advice at all from you experts out there would be most welcome. David Brown Somerton, Somerset, UK
sundial motto for clergy
For a protestant - words spoken by the first protestant, Martin Luther on posting his 95 Theses on the door of the Worms cathedral - the diet of Worms. Also very appropriate for a sundial. I did one for a Methodist minister in N. Ireland with this on it - also v. appropriate for him in that situation. Here I stand, I can do no other David Brown Somerston, Somerset, UK
J.Carmichael stone technique - pics
I sent an email to the group sundial@rrz.uni-koeln.de a couple of days ago, with two attached files of photos. Did anyone receive them, or should I send again? David Brown Somerston Somerset, UK
Re: The J. Carmichael stone technique...
I rarely use the stuck-on paper technique (using wallpaper adhesive), and never on slate (which is easy to 'draw' on accurately with a light scribe and whose marks are easily rubbed off at later stages). However, two examples spring to mind. The first was on sandstone for an analemmatic dial for the sea-front at Minehead, Somerset, UK, when I had to incorporate the names of 40 or so Parish Councils around the perimeter of the 6m diameter dial. By printing out the names full size (letter x-height about 5 cm) I could be sure that I was going to get consistency in letterform and that all the letters would fit into the very resticted space avialable as well as meet up exactly at the end of the circle. It was also a hugely time-saving technique. The other occasion is one that is still in progress. It's on a cuboctahedron of Portland stone (a fine, hard limestone), based on a 22cm (9") cube. There are 4 dials (direct south,east,west and an analemmatic dial on top) with an equation of time curve on the north face. the other 8 smaller triangular faces have carved motifs of some releveance to the recipient. The reason for using the paper technique was to save time having to draw out all the details again, having already drawn them full-size in the preparation/design stage. The big snag that I now find is that the drawing-paper thickness is comparable with the width of some of the details on the dials, and as a consequence, the paper has to be cut away before the stone can be got at to carve the detail, resulting in time lost that I had previously gained! How it will all turn out after colouring in enamel paint remains to be seen, because part of the purpose in keeping the papar in place is that it will act as a mask when I do the colouring. I may even attempt in-filling the incisions with epoxy resin. We shall see. Pics available if anyone's interested. David Brown David Brown Sundials, Somerton, Somerset, UK
SONNE
Good program, and I use it frequently. Quite often, when drawing out large sundials for cutting in stone, I need to have co-ordinates of date curves so that I can get the shape correct, particularly at hours well before and after noon. Is it possible to extract co-ordinates (cartesian or otherwise) from the Sonne program? If so, how? Alternatively, can I get the computer to print out versions to a (pre-determined) scale larger than A4? If so, how? David Brown Somerton, Somerset, UK
Horizontal gnomons on Roman dials
It is misleading, surely to talk about horizontal gnomons on roman Berossus-type dials. The only purpos of the metal 'gnomon' is to provide a support for the nodus tip, which is the only part of the 'gnomon' that it used for telling the time and/or date on these dials. The support could come in from any angle - even by convoluted/spiral/twisted or whatever so long as there was a point acting as a nodus at the 'centre' of the dial to cast the shadow correctly. David Brown Somerset UK
Sundials on Bridges
Does the cubical dial on Maud Heath's causeway in Wiltshire qualify? David Brown Somerton, Somerset, UK
Latin translation
With a little help from friends. Your inscription should read: solem quis dicere falsum audeat?and it comes from the first book of Virgil's Georgics, in a passage where he praises the usefulness of the sun in weather-forecasting! It means "Who would dare to declare the sun false?" Immediately before your inscription come the words "Sol tibi signa dabit" i.e. The sun will give you signs. That might come in handy for you if you are looking for a suitable inscription.David Brown
Time in Sweden
Dear Friends, I am designing a sundial for a client in Stockholm.(Time Zone +1). Does Sweden have a daylight saving regime, and if so, what is it called (as 'BST' in UK), and is it +1 or +2 on GMT? David Brown Somerton, UK
Re: Calculating dimensions from perspective pictures; reverse engineering
David Brown Somerton, Somerset, UK
Reverse Engineering - Marlborough, Wiltshire, UK
Made by John Oliver, probably, in 1653, described as being in its original location and declining approximately S50E. From a wax 'rubbing' of the dial and 'working backwards', the declination is close to S45E although some of the lines are a little wayward. I am undertaking the construction of a gnomon that will be fixed to the wooden framework (on the outside) and not touch the ancienty glass at all. I needed to look, therefore at the outside of the window. Whilst doing that, I took a closer look at the dial glass, especially at the place where the gnomon had been originally attached to the lead work. There has been some restoration done on the dial in the last couple of years to support the glass which was cracked in a number of places. Imagine my surprise and delight when I discovered small numerals, 4 5 in an old style of script, scratched into the glass on the outside, just where the root of the gnomon would have been attached to the lead. I would be interested to know whether this was just a coincidence, or whether it was the practice of some makers, or just John Gilbert, to inscribe the dial declination on the dial. David Brown Somerton, Somerset, UK
Re: Reverse Engineering
David Brown Somerton, Somerset, UK
Inferior Polar Dial
What hour lines should be inscribed, and in what places, on an inferior polar dial for latitude 52N? The centrally-placed gnomon is 13 units high, the overall plate width (east-west) is 37 units and the north-south plate height is 26 units. Thank you for the various replies sent in (4). I clarified the term 'inferior' later on that day thus: "Inferior"..Think first of a 'normal' polar dial, parallel to the polar axis, aligned E-W but face open to the south i.e. that part of the celestial equator above the horizon. Now consider the underneath of this polar dial, face open to the north, facing that part of the celestial equator which is (mostly) below the northern horizon. You've now got an 'inferior' polar dial. The term is used in a document I came across recently (on the internet). I suppose that an equivalent description would be 'a polar dial facing north' or a direct north dial inclining at an angle to the horizon equal to the latitude of the place (52 deg in this case). Yes - it will be latitude independent, but I included that detail so that it would pin down the discussion a bit. The BSS Glossary also defines 'inferior' as "refers to an event on the celestial sphere below the horizon. Opposite of superior." Let me now tell you the reason for my enquiry: I was looking at the website of the Museum of the History of Science, Oxford (epact.mhs.ox.ac.uk/catalogue), and brought up the details of Nicolaus Kratzer's portable polyhedral dial (1525) made of gilt brass which he presented to Cardinal Wolsey (Inventory No. 54054). It appears to have been made for latitude 52 deg. N There are dials on nine faces. One is described as an 'inferior polar dial, with lines marked 4,6,8. This puzzled me - what is the sense of only hours 4,6,8 on any dial? The illustration given on the museum's web page is not clear enough to get any detail other than to see that the north face is not visible. However, a postcard I bought at the museum some years ago does show the north face and knowing the overall height of the dial (100mm) I estimate that the height of the gnomon on the inferior polar dial is 13 mm. It seems that the lines for 4 am ( to the west and 8 pm to the east) are wrongly positioned - they should be about 22.5 mm away from the centre of the dial, and are nowhere near this distance. A further puzzle - why did Kratzer mark the line on which the gnomon lies with a 6? It should be 12 (midnight!) if it's going to be anything - or was it because 6 comes exactly between 8 and 4? A blunder, perhaps? More measurement pending.. David Brown Somerton, Somerset, UK
Re: Inferior polar dial
Thanks for your interest, Chris David Brown Somerton, Somerset, UK
Inferior polar dial
What hour lines should be inscribed, and in what places, on an inferior polar dial for latitude 52N? The centrally-placed gnomon is 13 units high, the overall plate width (east-west) is 37 units and the north-south plate height is 26 units. David Brown Somerton, Somerset, UK
Re: EarthDial project
David Brown, Somerset, UK [EMAIL PROTECTED] www.DavidBrown Sundials.com
Re: Great clock value
Re: Shadow program fixed
David Brown
Re: Sandblasting and beadblasting
John...Have I missed some info? What is your technique for matte gold plating of brass sundial parts? How delicate are the finished parts (for fingering,etc) I'm sending this from Raleigh NC, where I am visiting (from UK)for 1 week. I went to Savannah yesterday - passing through en route from Kitty Hawk and Kennedy space Centre). I understood from the tram tour guid that there was/had been a sundial in Johnson Square(?) in 18th century. Does anyone know anything about this? I couldn't find it. Also could find no sundial at Kennedy Space Centre. My fault or theirs ??? David Brown DavidBrownSundials.com [EMAIL PROTECTED] -
Re: More on etching
Tony...Please send me etching technique notes and jpegs. Thanks. David Brown. -
Re: On Meridian dials
Re: Test
OK here. David Brown -
Re: Sundials in Manchester (of all places)
Thanks, Mike, for the photos. Whatever next? Good luck to them! David Brown -
Re: Sundials in Manchester of all places
Mike - thanks for your info on the Mancunian dials. Looks like life will be interesting for the designers if they havn't done their homework! -
Re: Sundials in Manchester of all places
Fascinating. Weird and wonderful! I hope that the architects/designers have got some good gnomonic science/sense behind their designs. I have three experiences of designers/architects and sundials. 1. The large vertical dial (2 m square) on top of a one-storey building needed to be observed through a skylight. the gnomon was about 5 cm thick. All the hour liones radiated from a point. i.e. no allowance made for gnomon thickbess. Not to mention that the hour-lines were all drawns fro a different latitude than for the place of use. 2. A whole array of very large sundials spread across the city of Bristol had vertical gnomons and all hour lines at 15 deg.! Never built - perhaps it was as well. 3. A big project on-going in the middle-east. Very big plaza dial with 100 ft high gnomon had a powerful laser beam at the top of the gnomon mast which was shinbe dwonwards on to conventional 24-hour hour-marks so that the time could be read at night. Pity the eyes of the unfortunate users who who look up to see where the bright (laser) light was coming from! Ah wellWhat are we 'experts' here for? David Brown 51.05N 2.74W -
Re: Sundials in Manchester of all places
The answer to all John Carmichael's shadow shapener problems at Kitt Peak! -
Re: Sundials in Manchester of all places
I see that the caption to a photograph on the Manchester news web page (www.manchesteronline.co.uk/news/stories/Detail_LinkStory=48875.html) tells us that Craig Martin's sundial works at night, Wow! -
Re: Sundial web pages and controlled vocabulary
I'm all for making life easy and interesting for those who are novices in the mysteries of dials and dialling. I'm still learning! Have a look at DavidBrownSundials.com. I could add a few key words, possibly. David Brown 51.05N 2.74W -
Re: My New Website
JohnI can open all the pages saisfactorily except the one on prices and types of sundial. I'd be glad to know whether you can view all of my wesite without flaw. David BrownSundials.com -
Re: My New Website
Thanks. David -
Re: sundial classification
I don't think you should include 'garden' as a type of horizontal sundial - or any! Gardens could have as many types of dial as exist! David Brown 51.05N 2.74W -
Re: My New Website
I couldn't get the Sundial Types and Prices page to download. Is there a glitch, or is it me? Glad youi're still active, having met you at BSS conference at Dunchurch (in 1999?). Have you got a photo of your Kitt Peak dial from the air (or even from the ground)? David Brown 51.05N 2.74W -
Re: Lady wants Polyhedral Dial
I have taken up the challenge of a desk-top polyhedral dial with Esther Hope and work is progressing nicely! She is very content with work done so far. David Brown -
Re: Lady wants Polyhedral Dial
John. Are you sure the email address of the polyhedral lady (Esther Ammon) is correct? David Brown -
Re: aries
Nice point, Frank. The virtue of using astrological symbols to signify dates on curves on a dial is that they are much easier to carve than a seriies of numbers/letters, and take up less space. They're also pictorial, which adds to the fun of a dial. David Brown 2.05W 52.75WN -
Re: Aries
I often include Aries and Libra symbols on dials I make. I'm sure it is, or used to be, common practice. David Brown 2.05W 52.75N -
Re: Question for help
Presumably you're interested only in the genuine article - not new heispheriums? David Brown 51.05N 2.75W -
Re: Another question for help
Have you got the plaster cast dial that's in the Science Museum, London? It's a plaster cast of one at Hever Castle. David Brown 51.05N 2.75W -
Re: hour numbers written in reverse
It could just be an aberration in the making of it. A long time ago I made a dial for an 80th birthday present. It wasn't until after the presentation and delivery of developed photos that I realised that I had put the hours as 5,4,6,7,8.. And so it remains! -
Re: Analemmatic Date Line
I always do mine clockwise. The hours go clockwise (N. hemisphere), and visually it would jar the senses to have one sequence go clockwise (hours) and the other anticlockwise (months). Gnomonically/astronomically speaking, it doesn't make any difference. David Brown 2.05W 52.75N -
stainless steel.
Thanks to all those who have contributed to the discussion on stainless steel. David 2.05W 52.75N -
stainless steel sundials
I am in the early stages of a project that is likely to involves the making of a stainless steel sundial - possibly equatorial, possibly armillary sphere. I ned to get in touch wit a stainless steel worker, preferably UK-based, preferably who has experience in sundial-making. The project might involve stainless steel castings. Could be a 'futuristic'/modern design Can anyone give me a lead? David 2.05W 52.75N -
Re: Oct 2002 Poptronics LED Sundial
Could I also have a copy? David Brown [EMAIL PROTECTED] -
Re: Thew patent dial
Thanks, Willy. David -
Re: Thew patent dial
http://www.biol.rug.nl/maes/zonnewijzers/en/whitehall-e.htm . Is this address correct? I couldn't locate it. david Brown
Re: Paper dial faces
Why not print a copy of your image the right way round on a transparency sheet, then photocopy the transparecy image the wrong way up? David Brown -
Re: Starting a sundial business
Take a look at my website - DavidBrownSundials - for examples of dials done in stone- all by hand. Expect 'life' to come into your dials only with hand-cut features. Much time spent per dial - typically a week to make for a straightforward horizontal dial - not counting the hours involved with design and consultation with the client. Prices according to time spent/complexity, size etc. etc. But laser-cutting/sandblasting - NO -
Re: Conference Travel Tip
port...originated in 17th cenrtury, referring to the side of a ship usually facing the port (the place where a ship could load/unload. larboardMiddle English lathebord, lad(d)borde, probably 'the loading side', but influence be 'starboard'. laden = to load, LADE + bord, the ship's side, BOARD. details from Reader's digst Universal Dictionary!! Any use? David Brown
Re: Conference Travel Tip
CharlieWhat exactly is it that you do not understand? David Brown -
Re: Conference Travel Tip
Re: time scale labels
My feeling is that the simpler you make the dial, the more likely it is to be used/understood. So.make a dial with only one scale of hours, arranged to show local time i.e. noon line vertical, and noon (preferably) or 1pm marked on that vertical line. then in the equation of time correction curve, allow for longitude in the scale of minutes correction (the curve is 'lifted' on the minutes axis by 4minutes for everey degree west of the time zone standard meridian, and lowered correspondinglyfor every degree east. Then put a short instruction clearly on the area of the correction curve that says (if in UK, for example, for a dial that has 12 marked on the local noon line) GMT: apply minutes. BST: + 1 hr. David Brown, Somerton, Somerset, UK -
Re: A new sundial
Please send info to me when available [EMAIL PROTECTED] -
Re: Conference Travel Tip
The names port and starboard come from ancient ship-lore. Most people are right-handed, They would steer the ship with the right hand using a plank - a steer-board, down the outside of the ship near the stern. Hence steer-board, and right-hand side of ship. The other side of the ship would be uncluttered, and so would be the side of the ship to come alongside in the port. Hence left-hand side of ship and port side. Better to understand the reason than have fancy mnemonics etc. David Brown, David Brown Sundials, UK -
Re: Conference Travel Tip
Hi, JohnThe port side is the left side of the aircraft/ship. David Brown. David Brown Sundials, UK -
Re: Mosaic
Have you also checked out the roman mosaic which includes a sundial at Brading, Isle of Wight, UK. The central subject is a black-bearded astronomer seated by a pillar with a sundial on it, pointing with a stick to a globe below it, and a vase with what seems to be a pen sticking out of it on his other side. It has been suggested that he is Hipparchus, the first great astronomer. I do not have a picture of it, and have so far been unsuccessful in getting any picture of it on the web. Can anyone find a picture? David Brown -
Re: seminar
Tony Moss - nice to hear of your offer re OHP materials and PDF/JGIF diags on Adobe Illustrator. Also interested in your JPEGs of shots of the 3D version. Please send whatever you can. Thanks. David Brown -
Re: (no subject)
Wall declination using carpenter's square. Look in Waugh, and follow the method suggested where he has a nail through a vertical board pressed against the wall. David Brown -
Re: seminar
Tony Moss - nice to hear of your offer re OHP materials and PDF/JGIF diags on Adobe Illustrator. Also interested in your JPEGs of shots of the 3D version. Please send whatever you can. Thanks. David Brown -
