ScientificAmerican1902-02-01.jpg Scientific American 1902-01-25ThumbnailsScientific American 1902-02-08Scientific American 1902-01-25ThumbnailsScientific American 1902-02-08Scientific American 1902-01-25ThumbnailsScientific American 1902-02-08Scientific American 1902-01-25ThumbnailsScientific American 1902-02-08Scientific American 1902-01-25ThumbnailsScientific American 1902-02-08

Survey work of the Isthmian Canal Commission engineers at Nicaragua. Gaging a stream. Leveler and asistant. Sediment gage car. Surveying party in camp. Aerial trolley car for use in river gaging.



Source: Steve Kirch, collector, and creator of a great website about SCIENTIFIC AMERICAN in the past

Restoration by: magscanner