Interest in the whole subject now rapidly increased, and extended to agriculturists and local observers. Yearly excavations were carefully scanned and even special researches were carried on in the interests of science. Strobel, a professed naturalist with remarkably precise and accurate habits, devoted his great energies to the elucidation of the organic remains, especially the rich and varied products of the peaty bed (terra uliginosa) at Castione, in which the piles were detected. Pigorini, on the other hand, was an archæologist pure and simple, but endowed with great ability and much fertility in the correlation and generalisation of facts—qualities which have since gained him the chair of archæology at Rome, which he now fills with so much distinction. Thus associated these two men may be said to have developed a new school of archæology, especially anent the terremare, having as its primary and indispensable object the collection of authenticated data, without which, they asserted, no deductions however brilliant could be scientific.
In the course of researches conducted by Strobel at Castione, during the years 1862 and 1863, he observed that the piles were placed in a sort of basin, either natural or artificial; that they supported transverse beams over which clay floorings had been placed; and that they were more thickly set towards the margin, and slanting, as if to strengthen the inner superstructures. Moreover, he proved that the supposed peaty formation (terra uliginosa) had nothing in common with true peat, but was simply a subaqueous deposit of ordinary earth, associated with decomposed organic débris. Another terramara in Parma having similar characteristics to that at Castione was investigated in the following year by Pigorini, and thus the theory of an occasional palafitte converted into a land-dwelling seemed to them to be confirmed. Previous to this the stratification of the beds—one of the most remarkable features of these deposits—had not excited any unusual surprise, but now it began to be commented upon.
These and some other noteworthy observations here and there coming to light induced Strobel and Pigorini to issue a second report on the terremare of Parma. (B. 89.) But in this brochure, which appeared in 1864, there does not appear to be any striking departure from the views expressed by the authors in their previous report. They asserted that the people who constructed and inhabited these dwellings were a nomadic or agricultural race, belonging to the Bronze Age, and were probably allied to the Swiss lake-dwellers; and that their habitations varied in structural character according to the exigencies of the site chosen. No significance was attached to the piles at Castione and elsewhere, beyond supplying a proof that different methods of construction had been in use, the adoption of which depended on local conditions. The composition of the strata as "earthy beds, now ashy, now yellowish, now reddish or black," and their peculiarly wavy arrangement, were supposed to mark merely a variety.
The terremare now became a controversial focus between the adherents of the old and new schools. To the former Cavedoni, Coppi, and subsequently Crespellani, lent their influence; while the latter were reinforced by Boni, Canestrini, Calegari, and Chierici. Amongst all these, during the next few years, Chierici stood pre-eminent. Already an ardent collector of the antiquities of his native country, he found in the mysterious terremare a congenial field and a new outlet for his love of practical research. For minute observation and lucid exposition of the phenomena observed in explorations, Chierici had few superiors. To him must undoubtedly be assigned the next great contributions towards the elucidation of the terremare problem. Observing in several instances that an earthy dyke of a rectangular shape, with a ditch outside, surrounded the terramara mound, and that upright beams, or traces of them, were to be seen in all parts of the deposits, he suggested that these were normal features in their structure. Although some of his contemporary explorers had incidentally noticed piles in a stratum different from that in which their original discovery was made at Castione, and even recorded the fact (B. 407, p. 7), it remained to Chierici alone to interpret the true significance of the discovery. In support of the theory of universality of the palafitte system, he showed that in many cases the piles had entirely disappeared by decomposition, and that the only traces of their existence were the holes they had occupied. Some of these, indeed, had subsequently become filled up by infiltrated matter, so that on section they presented the appearance of inverted cones. On this point he relates that in one space measuring 210 square metres he counted no less than 124 "buche di pali." (B. 206, p. 9.)
It must be remembered that, previous to this, archæologists had no clear notion of the order or relative position of the products of different ages and races, and the same confusion extended to the terremare. For instance, at Castelnuovo, Chierici seemed puzzled at finding, underneath a Bronze Age terramara, indications of an older period. At Campeggine, on the other hand, objects of the early Iron Age appeared, but chiefly in the upper strata, while Etruscan remains had been recognised in several instances.
Another point to which Chierici's attention was directed was the frequency with which rectangular enclosures were disposed so as to have their four sides facing the cardinal points; and this orientation within certain limits, varying, it would seem, according to the direction of the sunrise when the settlement was founded, he considered also applicable to all the terramara villages. On this point see also Helbig. (B. 308.)
In his famous theory of the structure of the terramara villages (B. 206) Chierici conceived the idea that they had been constructed over artificial basins to which a running stream was made to flow so as to convert the bacino into a pool of water. This pool was surrounded by an earthen dyke inside of which a wooden platform was erected on piles and covered with a layer of clay. Huts were then erected over this platform at regular intervals, and the refuse from them was thrown, by means of holes here and there, into the space below. The water entering at one side of the enclosure made its exit at the opposite side. Thus the space below the platform was more or less occupied with water, and the débris thrown into it became arranged into sedimentary strata, and so continued to accumulate until the entire space was filled up. When the accumulation of débris reached this extent it became necessary to elevate their floorings, and this was done by repeating the same process at a higher level; and in this manner Chierici accounted for the successive platforms and palafittes which were to be met with in the terramara beds.
Thus in the hands of Chierici almost every feature of the terramara deposits excited fresh interest and an eagerness for further inquiries. Piles or their traces were found almost immediately in all the stations wherever they were carefully looked for. In 1872 Chierici and Mantovani explored two stations, one at Monte Venere and the other at Monte, in which were found not only the dyke surrounding the basin and palafitte, but, in one of them, three series of piles, one superimposed above the other, thus clearly showing that when the spaces around the piles and underneath the platform had got filled up with débris, a second palafitte had been resorted to, which in its turn had been succeeded by a third. (B. 233 and 247.) It was on all hands acknowledged that in many parts the peculiar stratification of the layers in certain beds could only be accounted for on the supposition that water had somehow to do with the sorting of their ingredients, as floating materials, such as bits of charcoal, were often eliminated and formed separate layers. So far Chierici's theory might be taken as offering a complete explanation of the phenomena. But the deposition of the higher portions of the mound remained to be accounted for, as it was difficult to conceive of pools of water at the requisite heights. A still more formidable objection was the impossibility of transporting water without the intervention of a system of hydraulics to sites placed on elevations far above the level of any adjacent streams, and of this class several had been known, as at Monte Venere, Roteglia, Castellaccio, etc. (B. 407, p. 9); yet, in most cases, they also contained the palafitte and dyke. This was the weakest part of the theory and found few supporters, but in other respects every additional discovery only tended to confirm it. Strobel, however, declined to believe in the universality of either dykes or palafittes. Thus, writing in 1874 (B. 267), he says: "At the conclusion of an article which I wrote in 1872 on shells of Unio found in the marière, etc., I asserted that the terremare, those prehistoric settlements, were terrestrial; that in some of them man lived in pile-dwellings on dry ground, in others he dwelt in tents or huts; and that in some of the terramara beds earthworks can be seen, which may have been used as dykes or bulwarks, and which in all probability were fortified with ditches." After showing how impossible it would be for the terramaricoli of Roteglia and Castellaccio to have pools of water at such an elevation as they had been, he goes on to say: "And here I may be permitted to raise my voice against those who imagine that prehistoric men, and more especially those of the marière, and of our terremare and pile-dwellings of the Bronze Age, always and everywhere followed constantly one uniform and invariable order in arranging their abodes, as if they were inferior to the animals, nay, even to the invertebrates, who modify their constructions according to circumstances. But, in fact, there is much less uniformity in these terremare than is often found in the dwellings of animals; therefore I maintain logically, that even prehistoric men changed their mode of living according to place, time, and circumstances; and that the terramaricoli did not live solely in pools of water, as some assert, but had settlements both in the water and on dry land, and that the terramara beds are the results of the latter. In some of the terrestrial settlements they probably had pile-dwellings, while in others they lived in huts or tents. Some at least of the land settlements were defended by dykes and ditches." (B. 119, 2nd ed., p. 402.)
Pigorini, on the other hand, looked favourably on the major portion of Chierici's generalisations, and in the course of explorations conducted by him at Casaroldo in 1874 (B. 266 and 297) he found everything not only in harmony with his views but some additional facts that seemed to strengthen that portion of his theory in which he maintained that the palafitte was the normal method adopted in the structure of the terremare, whatever the nature of the locality might be in which they were constructed. Thus at Casaroldo, although there was both a ditch and a dyke surrounding the basin containing the palafitte, it had no peaty understratum (terra uliginosa), as at Castione, but a substance precisely identical with the superimposed deposits. Here also there were traces of piles on a higher level.
Almost coincident with the publication of Chierici's theory of the terremare, in 1871, was the International Congress of Anthropology and Prehistoric Archæology at Bologna, which gave an immense impetus to such studies. Indeed, the decade which followed may be characterised as the Augustan age in the department of prehistoric archæology in Italy. The remarkable discoveries in the old cemeteries of Bologna, and in Etruscan tombs elsewhere in the Circumpadana district, together with the increasing number of prehistoric stations in lakes, turbaries, caverns, etc., greatly widened the field of research and added to the difficulty of deciphering, from amidst the endless overlappings of their remains, the history of the various civilisations which formerly characterised the country. In order to facilitate these studies the Bullettino Paletnologia Italiana was established at the commencement of 1875, under the joint editorship of Chierici, Pigorini, and Strobel. This periodical has done much good and is still in a flourishing condition.