Hi John,
Thanks to Sara, Fer, and Gianni for helping us keep the types of dials clearly
labeled. I am sorry for being one of those that contributed to the confusion.
I understand now why azimuthal dials must have a vertical style.
The Glossary is nicely done. I like how you linked key words so a mouse click
gives more information. I do have a comment about the bifilar definition given
in the glossary. It reads:
bifilar ~: invented in 1922 by Hugo Michnik in its horizontal form, although
it
can be on any plane. The time is indicated by the intersection on the dial
plate,
of the shadows of two wires stretched above and parallel to it. The wires
often
run E-W and N-S, with their (different) heights above the plane being a
function of the location of the dial. It has equiangular hour markings, and
hence can be delineated to show many kinds of hours.
The ratio of wire heights must be just right for the hour angles to be equal.
Fred Sawyer deals with the special case of equiangular hours in a past issue of
the Compendium and in Sciatheric Notes #1. While the original Michnik dial was
equiangular, Fer de Vries has shown in an early issue of the BSS Bulletin, that
the hour angles are not required to be equal. The last sentence of the bifilar
definition could be worded to reflect this expansion. The last sentence could
read "It can have equiangular hour markings, and can be delineated to show many
kinds of hours."
Warren Thom (41.649N 88.096W)
John Davis wrote:
> Hi All,
>
> I'll buy this, and put in in the next draft of the Glossary. I really don't
> want a different term for every possible type of dial!
>
> Regards,
>
> John
> ------------------------------------------------------------------------
> Dr J R Davis
> Flowton, UK
> 52.08N, 1.043E
> email: [EMAIL PROTECTED]
>
> ----- Original Message -----
> From: Patrick Powers <[EMAIL PROTECTED]>
> To: sundial <sundial@rrz.uni-koeln.de>
> Sent: 27 February 2000 20:28
> Subject: Re: sundial taxonomy
>
> Message text written by "Sara Schechner"
>
> >As an alternative approach we could get round this by specifying
> the angles of universality. e.g., UNIVERSAL 60°N - 10°S<
>
> I would go with this. I don't like the idea of something being 'partly
> universal'. It seems to me things are either universal or they are not.
> [A similar problem also can occur with use of the word 'unique']. If one
> states the boundaries within which the device is universal that is far
> better to my way of thinking. But then maybe I am a pedant.
>
> Patrick
