Atrato (Atra`to) , a river in Colombia which flows N. into the Gulf of Darien; is navigable for 200 m., proposed, since the failure of the Panama scheme, to be converted, along with San Juan River, into a canal to connect the Atlantic and the Pacific.
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Atomic weight * A`treus