The arm holding an egg thought to be related to a statue found at Maison Chaluleau - when was the original finding 'of the arm of this statue' of Venus?

This is a sentence from a paragraph I wrote last year, while trying to work out - archaeologically speaking - what was found and when at Rennes-les-Bains. I have since come across a testimony of someone who was in person witnessing finds in real time, and this gentleman published his account. What this tells me is that the artefacts and archaeology often referred to were seen before at least 1872. This account comes from one M. A. Cumenge who published in 1862 in the bulletin of the Literary and Scientific Society of Castres (pages 334 to 342) about his travels to Rennes-les-Bains. 

There will be more to follow - but this will suffice;

"Cinerary urns one meter high; a piece of carved marble, with a mutilated inscription, with characters engraved by skilful hands; fragments 1 to 2 meters long of various mouldings in white dllalie marble; a hand dried up by suffering, which lifts a cup in which a snake at rest coils; a woman's arm in beautiful statuary marble, in proportions much larger than life; and in the middle of these the ruins of a Roman temple, Celtiberian, Saracen, consular and imperial medals. All these objects, precious for Archeology, I saw carefully collected by Mr. de Fleury, owner of the baths of Rennes. He very kindly placed them at my disposal to study them and gather the elements of my report....

The temple of Rennes, of which I recognised the traces, the paving stones, the walls and various votive altars, still lay under a layer of plant soil at a depth of one meter and 50 centimetres. The pavement of the temple is made up of large slabs of 50 cent. thick, 25 wide by 35 long. It was while digging foundations and clearing the ground that we found the arm of a woman, holding an egg in her hand which she appears to be presenting to those present. It was the symbol of the divinity of these places dedicated to fertility, a belief which has continued to this day and which still makes people ask Rennes every year for the fulfilment of the dearest wish of a woman.... Aesculapius was still the God that people came to implore in Rennes. Certainly, if excavations were carried out in this place rich in archaeological treasures, we would find the body of this statue. We would see to which foot a big toe in white marble, which was broken by an unskilled workman, belonged. We would find the rest of this inscription. For which altars did these marble mouldings serve as ornaments and bases? I promised myself that one day I would see again this land which is not yet invaded by the habitations."

The famous arm is illustrated below. It is the arm some associate with a statue of Venus, one that Boudet found. Dr Gourdon associates all these finds with Maison Chalaleu. It is this Maison that has the legends of a buried Roman Temple viz;

"According to local legend there is a house in Rennes-les-Bains which for several generations belonged to a family with links to Abbe Boudet; the Cathary Family. … in this house there is a well called Puit du Cercle - it can be filled with water and emptied when needed. The Well gives access to a circular underground structure. This ancient structure only has half of it remaining, because the other half has collapsed as a result of flooding or landslides..."

The account comes from one M. A. Cumenge who published in 1862 in the bulletin of the Literary and Scientific Society of Castres (pages 334 to 342) his travels to Rennes-les-Bains.