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TWO SUNDIALS ON THE TOWN HALL OF SAINT-CYR SUR LOIRE

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There are two sun dials located on the Eastern wall of the town hall of Saint-Cyr, close to Turns. They are not exceptionally old, since they were made in october 1979. The author has engraved his initials : Y T. They are engraved on a stone plate, approximately 40 cm by 60 cm, a few cm thick. These dials are sitting on three legs, at each end of the east-facing wall of the building. They are about three or four meters tall. The layouts appear surprising at first glance, but they are completely traditional. They are just oriented a little unusually, which leads to this impression. The style is a North-South directed metal stem, and is therefore in this case almost parallel with the layout of the dial.

FIRST DIAL.
Only the time lines of 3 : 00 to 1 : 00 are drawro, because in the afternoon the dial is not lit up any more because of its orientation. It should be noted that the 3:00 line is superfluous, because at no time in this area can the sun give off shade so early the morning. Three other lines corresponding to 20 minutes (XX), 40 minutes (XL) and 50 miwutes (L) divide the ll:00 line. There seems to be an error in the layout of these lines: The distance between the 11:40 and 11:50 appears to be too small; it should be larger than the distance between 11:20 and 11:40 and smaller than the distance between 11:50 and I2:00. Diurnal arcs are traced monthly, indicating the days that the zodiac signs change, from 19 to 23, depending on the months and the summer and winter solstices. Let us recall that a diurnal arc is the curve followed by the end of the shadow on a given day (the curve on the equinoxes is actually a line!). Since the sun is at the same height twice per annum, the two dates are noted the end of each diurnal arc. One can read on this dial that the photo was taken either around October 20, or in the first days of March. It was almost 11:20 (with the Sun) . The spaces located between Iines III/IV, V/VT, VII/VIII, IX/X are represented as hollowed-out. In the space located between the Lines 11 and I2, only the parts corresponding to ,June, August, October and the part higher than the winter solstice are represented in hollow. The figures of this dial are noted in ubtractive Roman numeration known as "common". The phrase " LUCEM DEMONSTRAT HUMBRA " means: " the shade gives the light " or " the shade shows the light "

SECOND DIAL.
As on the first dial and for the same reason, only the lines from 3:00 to l2: 00 are drawn. It is to be noted (as for the first dial) that the presence of the 12:00 line indicates that the orientation is not completely eastward. The spaces located between the lines VI/VII, VIII/IX and X/XI are hollowed-out. The major characteristic of this dial is on the right hand side. It is, in fact a lunisolar dial. On the right edge, there is a series of reference marks corresponding to the number of days before (DIES ANTE) and after (DIES POST) the full moon. For the two-week period when the moon is sufficiently luminous, it will produce enough shadow on the sun-dial to read the hour. Representations of the lunar disk at Various stages are engraved in order to facilitate the reading. There are lines that branch out from these reference marks and cross the arc at numbers. These numbers correspond to the number of hours to subtract (lower part) or to add (higher part) to the hour read with the light of the moon, and to thus be able to convert it into solar hour. The Latin phrase on this one is "HORAS NON NUMERO NISI SERENAS" and its translation "I mark the hours only if they are serene" or "I mark only the clear hours". These are therefore two very beautiful sundials that you will be able to easily discover more about if you look at them more closely.