PHILOSOPHICAL SOCIETY OF WASHINGTON. 103 



Mr. G. K. Gilbert made a oommunication on 



LAKE BONNEVILLE, 



the great fossil lake of Utah. He described an ancient outlet 

 of the lake at Red Rock Pass near the town of Oxford, Idaho, 

 by which its waters were discharged into Snake River. Dur- 

 ing and since the desiccation of the lake, the land which it 

 covered has been tilted to the northward, in common with the 

 region of the L^aurentian lakes and the eastern and western sea- 

 boards. He further described a small movement along the line 

 of the great fault at the western base of the Wasatch Mountains, 

 by which the altitude of the mountains above the adjacent valley 

 has been increased at a date far more recent than that of the 

 ancient lake. (A full account of his observations will appear in 

 the publications of the U. S. Geographical and Geological Sur- 

 vey of the Rocky Mountain Region, in charge of Prof . J. W. 

 Powell.) 



Remarks were made by Mr. Antisell on the channel described 

 by Mr. Gilbert as affording temporary drainage; and by Mr. 

 Alvord on the appropriateness of giving to this basin the name 

 of Bonneville, who was the first to make a scientific exploration 

 of this region. Great Salt Lake for many years appeared on 

 the maps as Lake Bonneville. 



Mr. Alexander G. Bell, of Boston, made a communication on 



THE telephone, 



which he had invented, exhibiting and describing its construction 

 and explaining the principles on which it is operated. The sound 

 of the human voice received on a small plate of thin Russian 

 sheet-iron was conveyed by a telegraphic wire to a similar ap- 

 paratus in another room and repeated by the vibrations of a 

 similar iron plate. He stated that he made use of an undulatory, 

 instead oi an intermittent current, that no battery was necessary, 

 but that the variations of intensity were produced by the vibra- 

 tions of the soft iron plate, varying its distance from the poles 

 of an electro-magnetic helix just behind it. He stated that the 

 experiment had been successfully conducted, where the operator 

 and hearer were 153 miles apart. 



