"The first element in the art of construction, that is, stability, is manifested in these latter monuments. They do not come up to the fine _dolmens_, or to the monuments which followed them, but the principle on which stones should be laid together is already arrived at. The slab forming the covering is the first attempt at the lintel, the primitive base of architectural science. By insensible degrees the dimensions of the monument increased, the nature of the materials were modified, and, from the small elementary monument to the grand sepulchral _dolmen_, but one step remained to be made--a giant step, certainly, but not beyond the reach of human intelligence. "This step, however, was not accomplished suddenly and without transitional stages. We find a proof of this in the beautiful ossuary discovered in 1863, at Chamant near Senlis (Oise), on the property of the Comte de Lavaulx. This monument does not yet come up to the most beautiful of the class; but it possesses all the inspirations which suggested the form of its successors, of which, indeed, it is the type. "Almost flat slabs of stone, of a greater height than those forming the vaults, and of rather considerable dimensions, are placed on edge so as to form a square chamber. A partition, formed of stones of a similar character, leaving a space or passage between them, separates the chamber into two unequal portions. Some arrangement of this kind has been observed in most of the finest _dolmens_; it is found at a spot not far from Chamant, in a covered way known under the name of the _Pierres Turquoises_, in the forest of Carnelle, near Beaumont-sur-Oise (Seine-et-Oise). "At Chamant, however, the chamber was not more than 3 to 4 feet in height under the roof, which was formed of large flat stones, and was large enough to allow of a considerable number of bodies to be deposited within it, either in a recumbent or contracted position. Near them there were placed delicately-wrought flints, and also some fine-polished hatchets, one of which was of serpentine; another of large dimensions, sculptured after the fashion of the diluvial hatchets, appeared to me to have been prepared for polishing. "The researches which have been made have brought to light but slight traces of pottery, and the small fragments that I have examined do not point out any very remote age for this monument. Nevertheless, the investigation of this sepulchre, in which I was guided by a somewhat different idea from that of merely studying the monument itself, was not carried out with the exact care that would be necessary for collecting all the indications which it might have furnished.