The fountain design that was reproduced dates from about 1700. Many of the features displayed on the fountain are typical Bernini features, making it very interesting. The four energetic tritons that hover over the fountain, under the huge Neptune statue along with the rocky outcrops and torrents of water make the fountain an easy possible descendant of Bernini’s lost design. The artist may actually be Carlo Fontana.
Pope Clement XI, during his early years, made his own contribution to solving this issue. As a lover of antiques, when a granite column erected to honor Emperor Antoninus Pius was found in 1704, Clement XI wanted this column to be used as a part of the fountain. He thus became a cornerstone in the design of the Trevi. Diarist Valesio wrote about eh subject, saying, “Wednesday 13 August 1704. Today the site behind the Trevi fountain was measured, as His Beatitude is thinking of making a lavish façade for that Water that will include the great Antonine Column from Monte Citorio, and of making a spacious square in front of the fountain by drawing on the one behind it, in line with the church of Madonna dei Cruciferi”. Although the plans were never really implemented, the design was still part of the plan until at least 1730.
Valesio, on July 5th, 1728 wrote, “Monsignor Sardini, who comes from Lucca and is President for that Water went to persuade the Pope [Benedict XIII Orsini] to ornament the Trevi showpiece fountain and, when the Pope said he did not have the money, undertook to find it for him and the Pope gave him permission to do so; therefore His Most Noble Lordship, who fancies himself a poet, conveyed his thoughts to a certain sculptor from Naples, Paolo Benaglia, who had worked on stuccoes for the Pope. He is a man who takes risks, but has little or no knowledge of his art, and he has already made a model of the fountain that has been seen by many: the Blessed Virgin of the Rosary is seated at the highest point as His Beatitude wanted her there; below her to the left is the virgin “Trivia” whom the prelate’s mind has conceived as Pallas was conceived by Jove – with her right hand she points to the Holy Virgin, and with the left, to the water pouring from some rocks; on the right, there is the goddess Rome, armed and standing upright, and beside her, for no reason at all, a sow with some piglets; and in the group with the virgin “Trivia” there is a unicorn; this fine work will be crowned with an equally elegant inscription composed by the prelate himself… “Minervas aquas ministrat Trivia Virgo”; oh, and I forgot: so that the sow should not go hungry there are two oak trees, one on each side”. So here is another design, whose artist is unknown, but it is probable the designs are attributed to Benagalia.