Since well before there was awareness for solar energy, architecture has always interacted with light. The study of the apparent motion of the sun and shadows has interested man since ancient times. The construction of sundials is an ancient craft tradition balanced between poetry and geometry, and often involves the choice of the motto that bears witness to the culture of time. It also tells us a little about the owner of the house and creator of the sundial.
					Private house in the Garda hinterland. Made from acrylic on smoothed rustic plaster; the motto celebrates the warmth of friendship. Residence and bank headquarters in Brugherio Created with the master of gnomonics Mario Tebenghi; the motto invokes the themes of time and friendship. Concorezzo Parish Church The eighteenth-century parish church built by Cagnola and enlarged by Giovanni Muzio had a simple sundial over the doorway of the side entrance. In the mid 20th century, it was completely shaded by a row of locust trees. The new sundial was therefore built in the upper part of the south transept, to enjoy sun all day long. It was made with acrylics on original plaster; the stern motto chosen by the parish priest is associated with the austerity of the design. Porta Vittoria Residence The recent sundial calculated and constructed on the southern wall of the “tower” body of the complex has no motto, but a basic, “large scale” design: it is made of brushed stainless steel placed on the gelid Carrara marble wall, and has unusual measurements: overall height of 9.15 metres, width of 3.6 m and gnomon of 1.5m to indicate the time, the solstices and the equinoxes. Meridiana in Greco, Carlo Conti street This sundial is calculated and painted on a gable on the south side of the first 54 apartments complex, part of the PII Greco Conti that realized 40.000 square meters of public green, soccer field and bowls, parking, 114 new housing units, recovered the historical Cascina Conti for 17 social residences and realized a new paved and tree-lined pedestrian square of over 4.000 square meters. The sundial has an eastern "aspect" of 12,5° and the Latin motto "per aspera ad astra". Seasons sundial in the new Greco square This sundial, which we can call “sundial of the seasons”, does not indicate the hours but midday and the four characteristic moments of the year or the beginning of the seasons: on sunny days the iron ball placed above the lamppost creates a sharp shadow that is cast at these particular points namely: spring equinox (March 21) - Aries; summer solstice (June 21) - Cancer; autumn equinox (September 23) - Libra: winter solstice (December 21) - Capricorn. A line in blocks of white granite comes off the base of the light pole, on which the ball casting the shadow is mounted, and is directed exactly to the geographical North and the sun at noon casts the shadow of the ball, always in cyclic movement on it, more or less far from the base of the pole, according to the days of the year and the flow of the seasons. On the 4 brass panels that indicate the seasons, the inclination of the sun in degrees with respect to the floor is shown, in the four characteristic moments of the seasons and we read as follows: Aries (March 21) 45° 30'; Cancer (June 21) 69° 00'; Libra (or Libra) 45° 30'; Capricorn 22° 00'. We also note that the line joining the 2 symbols Aries and Libra are placed on the so-called “equinoctial” line perpendicular to the line in granite blocks on the floor facing North: during these 2 particular days, spring equinox - Aries - and autumn equinox - Libra - , the shadow cast by the iron ball placed at the apex of the lamppost runs exactly on it from when the sun rises until it hides behind the building in the West and sets. The angle of inclination of the Earth's axis in its rotation around the sun is equal to 23°26' degrees and in fact these are the degrees that separate the angle values between the 4 moments of entry of the seasons.