The inclosures, however, are described as being very similar to those in Western New York, and are probably simply fortified sites, common among rude people the world over, and such as were often erected by Indians. The remains on the upper Missouri and its tributaries are very numerous, and to judge from the brief description given us of them, they must be very interesting.13 This section has, however, been too little explored to speak with confidence of these works. As showing how much care should be exercised in this matter, we refer to the account given by Capt. Wilkes in his journal of the United States exploring expedition. Speaking of the mounds on the gravelly plains between the Columbia River and Puget Sound, he tells us that the Butte Prairies are covered with small mounds at regular distances asunder. Some of them are thirty feet in diameter, six or seven feet above the level of the ground, and many thousands in number. He opened some of them, and found a pavement of round stones, and he thought he could detect an arrangement of the mounds in groups of five, thus. Five dots It was his impression that they were the works of men, and had been constructed successively and at intervals of several years.14 This observation of Capt. Wilkes is referred to by many as evidence of the former existence of Mound Builders in this section. More careful research in recent times has established the fact that these mounds were certainly not erected by human hands, and no one else has been able to discover the supposed arrangement in groups of five. The pavement of round stones is common to the whole prairie. But the greatest objection is the number of the mounds. A population larger than could have found a living in the country must have been required to erect them, unless we assume that a great length of time was consumed in this work. Some other explanation must be given for these mounds, as well as for those mysterious ones mentioned by Prof. Forshey. This cut gives us a fair idea of the scenery of this section and the mounds.15 Mound Prairie.