SD-Mercier1

ย SD-Mercier2

SD-Mercier3

In 1922, Professor Hugo Michnik, invented the bifilar sundial. In the original version, the bifilar sundial has two non-touching threads parallel to the horizontal dial. The second thread is orthogonal to the first. The intersection of the two threads’ shadows gives the local apparent time.

Michnickโ€™s bifilar sundial (Wikipedia)

In sundial proposed here, the table is declinining and inclined, and threads are non-parallel to the table and non-perpendicular each other.

BSS comp EM threads

The threads: non-singular positions

BSS comp EM table

The table: declining & inclined

This dial is designed with an original software (HUGO,ย in homage to Professor Hugo Michnik) described in two French-language papers published in “Cadran-Info” (co-author: Dominique Colin).

Download:

M.E_C.D_Logiciel bi filaire

M.E_C.D_Logiciel HUGO

Note: The software version used here is newer and better than the one described in papers because it takes into account the threads length.

BSS comp EM lines

Software output: grey lines are hour lines position in the case of threads became longer.

BSS comp EM sundial table

The sundial table

BSS comp EM dates 1

October 11, 11h30 (TU+2) threads shadows in red

BSS comp EM dates 2

October 12, 12h00 (TU+2) threads shadows in red

BSS comp EM dates 3

October 12, 13h00 (TU+2) threads shadows in red

No cross !

BSS comp EM dates 4

October 11, 15h00 (TU+2) threads shadows in red

Cross is back !!

BSS comp EM dates 5

October 12, 16h00 (TU+2) threads shadows in red

BSS comp EM dates 6

October 12, 17h00 (TU+2) threads shadows in red

Sorry, no more sun in this place, in October !