Because the title is rather long I know without translation that it must contain a certain level of information. With translation it’s clear that the title is rather accurate and leaves no uncertainty about its content. As there is little text in the whole book it gives off the feeling of a city guide for visitors to Rome.
The book is parted into several chapters dividing the engravings in the different categories of fountains, giving the reader a better overview. Although I am not sure, it seemed to me, that the chapter at the beginning contains all important fountains and with every chapter the fountains grow wilder. Indicating that the engravings are sorted by their location in the city. The big ones near the center are in the first chapter and then with every chapter you move further away to the suburbs and then to the city boarder.
Considering the illustrations are engravings, made in copper, bronze or other soft metal, supports my theory of the city guide. While this technic of „making images“ comes with great expense, once made its long lasting and reusable for several times. The only down side of the city-guide-theory is the size of the book. The pages are quiet large (around A4), thus providing a lot of details but rather bulky to carry along.
In summary, the book remains me of a collection of engravings like the ones of Giovanni Battista Parinesi. Just like him, Giovanni Battista Falda is an artist of engravings and releases books with illustrations of Rome. The other famous one is about the places in Rome. Fulda was an apprentice to De Rossi, one of the most known at there time.