That there had been a great population once on these plains was evident from ancient cemeteries with elaborate monuments of an early but unknown people, of whom they are the only remains.  The tombs were rudely worked and decorated in prehistoric manner with devices of war or the chase; one device, which I copied, being of an archer shooting a wild goat, another of a warrior with a long broadsword and large square shield.  On some tombs were a crescent and star, the emblem of Constantinople; on a few a cross; but there was no attempt at a letter or other sign of language.  The entire absence of any ruins within the distance of our journeys (and by the report of the natives there were none in the country round about) made the presence of these cemeteries an archaeological problem to which I obtained no clue until some time later, on the surrender of Niksich.  We then discovered that a large part of the town was formed of houses—­huts would be more correct—­constructed on sledges, huge runners of timber, into which had been driven stakes, forming the frame of the house.  The stakes were filled in with willow branches, and the walls were completed with mud, the whole being roofed with thatch.  The forward end of the runners was perforated for a bar, to which oxen could be attached, and the house was evidently to be drawn from place to place, as the herds and flocks found food.  Of this nature had probably been the towns or villages to which the cemeteries belonged, and their existence still on the plain of Niksich, where they must have been built without any possibility of removal beyond the limits of the plain (which is only about ten miles in its greatest extent, and bounded by abrupt hills), was a curious evidence of the intensely conservative character of the population which had established itself there at a remote epoch.

The sledge houses at Niksich had never been moved, nor would there have been any object in moving them, for the remotest part of the plain was to be reached in a long hour’s walk, and the rocky setting of its grassy luxuriance, rising into higher land all round, by steep ridges, would have shown the builders that where the house was built, there it would stand.  On these great planinas there might have been a range far greater, but the presence of the cemeteries, which must have been the result of a considerable duration of residence, proved that the planinas now deserted, save for the summer haymakers, had once been held by a considerable population.  I desired to open one of the graves, but the superstition of the people, whom no inducement could prevail on to meddle with the dead, made it impossible to find workers to aid me.  I can only conjecture, therefore, from the emblems on the tombs and the rudeness of the reliefs, that they must date from early Christian times, probably the so-called Gallic (really Slavonic) invasions prior to Diocletian; and two or three huge and elaborate roadside crosses, cut from single stones and minutely decorated in relief, found nearer Cettinje, added to the conjectural evidence, for the origin of these was equally unknown to the present inhabitants.  We passed caves known immemorially as places of refuge and admirably placed and prepared for defense.  There is a great and untouched field there for prehistoric research.