ance disappointing. While here and there polished axes are found, the polished implement is the exception, not the rule, especially on higher ground. Again, comparing the chipped implements with those from regions abounding in flint, obsidian, and the finer varieties of the silex group, a large collection of them has a somewhat rude appearance. All this is due, however, to the material. The ancient Potomac dweller was restricted to bowlders of quartzite found in quantities inexhaustible all over his area, to veins of milky quartz outcropping here and there, and to an occasional quarry of soapstone. Types of pottery and impressions of woven fabrics contribute to our knowledge of the degree of advancement which the people had reached, and cast light on the tribal distributions. The most serious problem that faces the archaeologist in this area has been proposed by Mr. Thomas Wilson, in the evidence of the existence of two periods of occupation—the one Palæolithic and ancient, and the other Neolithic and modern. While the camp-sites along the water-courses yield abundance of finely chipped arrowheads, spear-heads, knives, polished implements, soapstone vessels, and pottery, the hills back from the river are wanting in the smaller, finer forms, but abound in coarser, flaked artefacta, mixed with broken implements and spalls.
The American Association.—The thirtyninth meeting of the American Association will be held in Indianapolis, beginning Wednesday, August 20th. The general sessions and the meetings of the sections will be held in the new and commodious State-House, where also will be the offices of the Local Committee and of the Permanent Secretary. The hotel headquarters of the Association will be at the Denison House, and the preliminary meeting of the Council will be held there on Tuesday, the 19th. Interest will be added to this meeting by the fact that it will mark the fiftieth anniversary of the organization of the Association of Geologists and Naturalists, the parent of the American Association. The sessions will continue till Tuesday evening, the 26th, and a meeting of the Council will be held Wednesday, the 27th; Saturday, the 23d, will be given to excursions; and the excursions, after the close of the meeting, will extend to August 30th.
The officers-elect for the meeting of 1890 are:
President.—George L. Goodale, Cambridge, Mass.
Vice-Presidents.—A, Mathematics and Astronomy—S. C. Chandler. B, Physics—Cleveland Abbe. C, Chemistry—R. B. Warder. D, Mechanical Science and Engineering—James E. Denton. E, Geology and Geography—John C. Branner. F, Biology—C. S. Minot. H, Anthropology—Frank Baker. I, Economic Science and Statistics—J. Richards Dodge.
Permanent Secretary.—G. W. Putnam.
General Secretary.—H. Carrington Bolton.
Secretary of the Council.—James Loudon.
Secretaries of the Sections.—A, Wooster W. Beman; B, W. Leconte Stevens; C, W. A. Noyes; D, M. E. Cooley; E, Samuel Calvin; F, John M. Coulter; H, Joseph Jastrow; I, S. Dana Horton.
Treasurer.—William Lilly.
Auditors.—Henry Wheatland, Thomas Meehan.
A Papuan Bridge.—A native suspension bridge, crossing the Yanapa River, is described by Sir William MacGregor, British Administrator of New Guinea, as being, considering its locality and the primitive situation of the inland natives of the district, a remarkable structure. Advantage is taken of the narrowing of the river by the projection of a rocky point, so that the bridge is only about seventy yards long. At one end it is chiefly supported by a large banyan-tree, whence it starts at an elevation of about fifty feet above the pool below. It descends then in mid-stream to about twelve or fifteen feet from the water, and rises to about twenty feet on the right bank. It is then suspended to a tree not strong enough to hold it firmly. The tree is, therefore, supplemented by a post put in the ground, and this is again strengthened by a cross-bar against the tree, fixed by stays extending backward to trees behind. The material of the structure is rattan cane. Fifteen canes are used to form supports, those not long enough to cross the river having been built up by knotting. The floor of the bridge is formed of four of these canes. Above the floor are two "guard lines" on
