I went to a semi vocational high school in NY called Brooklyn Tech. We were required back in those days (about 1964) to take much mechanical drawing and shops. I took one course called Descriptive Geometry in which we used the techniques you describe to build "Nomographs" or "Nomograms" whichever is the proper usage. Wish I could remember what text we used, I'd love to take another look at it.
regards, Tony DeVito Jean-Paul Cornec wrote: > Jim and John, > Indeed the "épure" is the result of projecting a > 3-D figure onto one or many planes according to > the rules of a branch of geometry we call in > french "géométrie descriptive". It is still used > in technical drawing and the method was very > popular in gnomonics before the PCs and the > hand-held computers. It is a bit obsolete now, > except for drawing the hours lines of the most > simple sundials for teaching purposes. > Good luck > > Jean-Paul Cornec > 22300 LANNION > FRANCE > > ---------- > > De : Jim Morrison <[EMAIL PROTECTED]> > > A : sundial <sundial@rrz.uni-koeln.de> > > Objet : Fw: epure > > Date : vendredi 4 juin 1999 17:13 > > > > John, > > > > My French is not what it once was, but I think > an épure is just a working > > drawing. > > > > Jim > > > > James E. Morrison > > Astrolabe web pages at: > http://myhouse.com/mc/planet/astrodir/astrolab.htm > > > ----- Original Message ----- > > From: John Carmichael <[EMAIL PROTECTED]> > > To: <sundial@rrz.uni-koeln.de> > > Sent: Friday, June 04, 1999 10:05 AM > > Subject: epure > > > > > > > Hi Dialists: > > > > > > I'm halfway through reading Rohr's sundial > book for the first time. In > > > laying out hour lines for many types of > sundials, Rohr uses a devise > > called > > > an "epure" (w/ an accent mark over the last > e.). He assumes that the > > reader > > > knows what this is. From the context I think > it must be some sort of > > > drawing tool or something like a trigon, but > I'm not sure. Does anybody > > > know? Is it still used by any of you? > Supposedly it aids in laying out > > > hour lines using graphic methods, but many of > Rohr's drawings are so > > > complicated, that they are very difficult to > understand. > > > > > > I'm so glad that my first sundial book was > the easy to read Mayalls' book. > > > I think that if I had started with Rohr I > would have given up! > > > > > > Thanks, > > > > > > John Carmichael > > > http://www.azstarnet.com/~pappas > > > > > > > >