Jacques Hillairet says in his Dictonnaire Historique des rues de Paris,(Historic Dictionary of the Streets of Paris) relating to the Quai Conti (where the tower was constructed) (p. 383):

A strong fortified gate, with two big towers on each side, was built some time after in the surrounding wall, about thirty yards south of the Hamelin tower . It was located at the present entrance to the Mazarine library, the staircase of which replaces the tower standing on your left when entering Paris. Thus in 1220, there was the Hamelin tower and the Hamelin gate.

Alfred Bonnardot in 1851 starts his tour of the rempart as follows :

P.37

"(...)the famous tower built c. 1200, named in an act of 1210 : Tornella Philippi Hamelini suprà Sequanam, then a century later : tour de Nesle ou Neelle, in latin Nigella. Its first name came from the provost of that time. The second name came from the adjacent mansion. It was located at the site of the present pavillion of the Institut is (...) Its two storeys were built on top of a kind of sloped sub-foundation which was flooded by the Seine waters. If this bedrock were still in existence, the raised up ground of the Institut would probably hide it completely. The Tour de Nesles is undoubtedly the most popular of all old Paris towers. A modern drama helped make it famous, for all that is wonderful is considered by the ordinary people as undisputed truth. But these so-called orgies supposedly to have taken place in that very tower and perfomed by Marguerite or Jeanne de Bourgogne - were far from being true. It is at least a truth hidden behind embellishements. A queen, leaving her palace at night, crossing an underground hall to give herself over to debauchery, ending in the moonlight by the mysterious splash in the river Seine of a throbbing corpse in a lugubrious bag all this is ravishing. But the cold-blooded archeologist who indulges in denying tales is tempted to send this sinister story to the devil.

As for me, I do not intend to reject this tradition as purely fanciful, but I find the story too vague, too obscure, to admit it as a real fact. It was passed on to us by poets and story-tellers, both kinds quite prone to exaggeration.

To us, this tower is simply the western part, the dungeon, of Philip-Augustus' wall. The ceilings of the three storeys were probably made of solid arches; maybe these vaults fell back on a central pillar. The flat roof of the tower was used as an observation point, where a sentinel kept watch on the river, the surroundings and of the royal castle of the Louvre. The three storeys must have contained weapons, appliances of war dating before the use of artillery. This was probably what it was used for since the time it was called Tornelle Philippe Hamelini, until the beginning of the 16th century. In the time of Charles IX, this tower was looked upon as a useless massive blackish contruction, clashing with the new part of the Louvre; and it was let out to private individuals.