P OP ULAR MIS CELL ANY. 



137 



pressed spine than the ancient form. In 

 another paper, Professor Morse, after refer- 

 ring to the fact that, although worked shells 

 were not uncommon in the shell-heaps of 

 Florida and California, none had been found 

 in the New England and Japanese shell- 

 heaps, exhibited specimens of the large 

 beach-cockle (Lunatia) from Marblehead, 

 Massachusetts, which had unmistakably 

 been worked by cutting out a part of the 

 outer whorl near the suture. To show that 

 this could not have been artificially broken, 

 he exhibited naturally broken shells of the 

 same species, both ancient and recent, in 

 which the fractures were essentially unlike 

 those of the worked shells. 



Who were the Mound-Builders ? Dr. 

 W. De Haas, after a careful examination 

 of the supposed connection between the 

 " mound-builders " and the ancient races of 

 Mexico, has come to the conclusion that it 

 does not exist. He considers that the for- 

 mer people were but little advanced beyond 

 the modern Indians, but that they were dif- 

 ferent. In the discussion that followed the 

 reading of Dr. De Haas's paper in the Ameri- 

 can Association, Judge Henderson objected 

 to the use of the term " mound-builder," as 

 one that conveyed a false idea. There is 

 no evidence, he said, which will justify us 

 in separating the ancient and more modern 

 races, not a single feature peculiar to the 

 so-called mound-builders. The speaker had 

 started out in the study of American archae- 

 ology with the impression that these people 

 were distinct and separate from the Indians, 

 but he had been compelled by the force of 

 facts to relinquish the theory. It was im- 

 proper to talk about these people as mys- 

 terious, for they were no more mysterious 

 than the Shawnees, the Natchez, the Tensas, 

 and other tribes. The cloth found in their 

 works was like that made by every tribe 

 from the Lakes to the Gulf, even less fine 

 than some, and their pottery was no better. 

 In short, the speaker said, in his judgment, 

 the mound-builders were the ancestors of 

 the Indians. 



M. Trouve's Electric Canoe. "La Na- 

 ture " gives the details of a series of ex- 

 periments made upon the Seine, at Paris, 

 in the latter days of May, with the elec- 



tric canoe and motor invented by M. G. 

 Trouve. The motor is composed of an im- 

 proved Siemens coil, which acts through a 

 Vaucasson chain and a Gallc chain upon a 

 thrce-bladed screw fitted into an opening 

 cut out of the rudder to receive it. It is 

 fixed to the upper part of the rudder, so 

 that it, as well as the screw, follows all its 

 movements. The motor employed in the 

 experiments was composed of two coils, 

 and, with its accessories, did not weigh 

 more than five kilogrammes (twelve and a 

 half pounds). It was placed in the stern 

 of a canoe, the Telephone, which meas- 

 ured seventeen feet ten inches by three 

 feet ten inches, and weighed one hundred 

 and eighty pounds. Two cup batteries of 

 bichromate of potassa, composed of six ele- 

 ments each, and weighing together sixty 

 pounds, were placed in the middle of the 

 canoe. They were connected with the mo- 

 tors by two cords, which served at the same 

 time as envelopes for the conducting wires 

 and as tiller-ropes, and which were fur- 

 nished with appurtenances for applying or 

 shutting off the current at will. The motor 

 is independent, and can be applied to any 

 boat. The first experiments were made on 

 the 26th of May, when the boat was worked 

 for about forty-five minutes by M. Trouve 

 and M. Tissandier, in the afternoon, and by 

 M. Trouve and others for about the same 

 time in the evening. A third experiment 

 was made on the 31st of May, in the pres- 

 ence of M. G. Berger, commissioner-general 

 of the Universal Electrical Exposition, M. 

 A. Breguet, of the " Revue Scientifique," 

 M. Hospitalier, M. Fricero, of the Russian 

 navy, and others. The Telephone, with 

 three persons in it, easily went up the Seine 

 six times for a distance of two hundred 

 metres, or six hundred and fifty feet, at the 

 rate of one metre in a second, and descend- 

 ed at the rate of two and a half metres in a 

 second. Other experiments were made on 

 the 2d of June, in presence of the Russian 

 Admiral Likhatchof and a number of spec- 

 tators interested in science or navigation. 

 These experiments recall a similar attempt 

 made on the Neva in 1839, by Jacobi. 

 He used on the occasion two Grove bat- 

 teries, each composed of sixty-four coup- 

 les of zinc and platinum, and presenting 

 a surface of sixteen square feet. The 



