Hello Michael,

The referenced article is actually titled "Equatorial Projection Sundial 
Projection Vectors" by Harold E. Brandmaier. It is about a specific type of 
sundial design, equatorial projection dials like the analemmatic and Foster 
Lambert dials. His technique uses vector and matrix math to solve for this 
specific type of dial with an moving gnomon on any plane, horizontal vertical, 
declining and reclining. It is not directly relevant to the discussion at hand. 
Do you want a copy?

I have Maynall 2nd Edition, not the usually quoted 3rd edition. This discusses 
graphical techniques for reclining declining dials and has formulae in the back 
for specific cases of inclined dials, declining directly north south and 
declining directly east west. Rohr  has six pages of complex math on reclining 
declining dials. I have scanned these and will send you copies.  

Regards, 
Roger Bailey


From: Michael Ossipoff 
Sent: Sunday, April 12, 2015 6:13 AM
To: [email protected] 
Subject: Does anyone have, or have access to, Compendium vol.12, #1, March 2005?


Alright, I realize that tryng to fix Wikipedia is like trying to bail-out the 
ocean with a thimble. But there's one little matter that I don't intend to let 
pass:

Wikipedia's Sundial article says (regarding Reclining-Declining dials):

"In fact it is only in the last decade that agreement has been found on the 
correct hour angle formula for this type of dial [...] Previous formulae given 
by Rohr and Mayall are not correct."

As I mentioned in a previouis post, the Mayall & Mayall formulas that Wikipedia 
quotes, miscopied, in a note to the article, give the correct answers, for 
arbitrarily chosen latitude, recline, decline-angle and time-of-day--right down 
to the last decimal place on the calculator.  ..when a few copying errors and 
variable-misinterpretations are fixed.

Anyway, Wikipedia's big emphasis is on citation of notable sources, especially 
for any implausible or surprising statements (like those quoted above).

The ony citation that's positioned anywhere near the abovequoted passage is to 
Compendium, vol. 12, #1, March 2005.   ...in an article entitled "Sundial 
Design Using Matrices".

The person who re-posted that passage after I deleted it won't answer my 
question about whether or not that article is the source of that statement (It 
could just have been intended as a reference for that sentence's mention of the 
use of matrices).

I'd like to get to the bottom of the matter of where Wikipedia got the 
abovequoted statements.

So, could someone take a look at that Compendium article, and tell me if it 
says anything that supports the abovequoted statements--and, if so,what it says?

I'd appreciate it if you'd paste its words on that matter into a post here, or 
an e-mail to me ( at [email protected]).

thank you
Michael Ossipoff
~ 26N, 80W


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