Thompson was now introduced by Jussomme to a chief who bore the name of "Big White Man." To this chief he explained that his business was not to trade, but to visit the various tribes of natives, in order to see how they could be more regularly supplied with arms, ammunition, and other articles which they much needed. Surprised and pleased at this agreeable information, the chief led the white man to his own hut, where he and his servant Boisseau were comfortably installed and entertained with all the rites of native hospitality. In company with Jussomme and McCrachan, Thompson then paid a visit to each of the five villages in turn. These, he found, were all built alike of domelike huts constructed of mud plastered over a framework of wood, each with an aperture in the centre of the roof to carry off the smoke of the fire and admit light to the solitary chamber of the dwelling. In front of each house stood a porch made of stretched bison skins, affording an approach to a doorway large enough to admit a horse. Passing the door, one entered a circular chamber about forty feet across, and, from the earthen floor to the aperture in the roof, eighteen or twenty feet in height. To the left of the doorway, sat the master of the house on a couch covered with buffalo robes. Before him was the fire, built in a circular space hollowed out of the floor, and surrounded by vessels of native pottery containing maize and boiled meat, the food of the household. Around the walls were a series of frame bunks about three feet from the ground, each of them enclosed by hides except for the front and made comfortable by a soft buffalo robe. To the right of the entrance were the stalls for the two or three horses which belonged to the household, to which every evening they were led back after pasturing on the plains. In the smallest of these villages, Thompson counted thirty-one such huts, in the largest one hundred-and-thirteen, each hut containing a family of from eight to ten souls. Surrounded as they were by fierce and violent enemies, the Mandans had constructed their villages with an eye to defence rather than to comfort. For this purpose a site was selected on elevated ground, so that no attack could be made from above. The houses were then built irregularly without regard for streets, and the whole village surrounded by a stockade of timbers at least twelve feet in height. On more than one occasion, Thompson learned, the Sioux had taken advantage of a dark and stormy night to approach the villages and fire the palisades. But the flames had no power to destroy the earthen houses; there were no straight streets down which the enemy could shoot; and, as a regular siege was beyond the power of any of their foes, the Mandans had hitherto escaped destruction.