author has availed himself he gratefully acknowledges his obligations. The author desires also to acknowledge the gratification he has derived from the many encouraging letters he has received, and the assistance which the numerous voluntary contributions of valuable information and important data have afforded him in the preparation of this work. ILLUSTRATIONS. 1. NIAGARA RAILWAY SUSPENSION BRIDGE... 4. PORTRAIT OF BENJAMIN WRIGHT 5. FIRST AMERICAN CANAL BOAT................ 6. DEEP ROCK CUTTING AT LOCKPORT ............ 7. VIEW OF THE AQUEDUCT AT LITTLE FALLS......... 8. PORTRAIT OF CANVASS WHITE*................ 9. VIEW OF THE AQUEDUCT AT ROCHESTER.. 10. COMBINED LOCKS AT LOCKPORT.. 11. PORTRAIT OF GRIDLEY BRYANT....... 12. HENRY CLAY'S FIRST RAILROAD RIDE........ 15. PORTRAIT OF MAJOR DAVID BATES DOUGLAS .... 16. CARROLLTON VIADUCT... 17. FIRST AMERICAN LOCOMOTIVE 18. FIRST RAILROAD PASSENGER CAR... 19. PORTRAIT OF BENJAMIN H. LATROBE................... 20. PORTRAIT OF COLONEL CHARLES ELLET, JR. .... 21. FAIRMOUNT BRIDGE... 22. ELLET'S BASKET RIDE OVER NIAGARA RIVER.... 23. CINCINNATI SUSPENSION BRIDGE. 24. EAST RIVER SUSPENSION BRIDGE........... • Engraved for this work, 1859. 7 CONTENTS. SURVEYING BOUNDARY LINES BETWEEN THE STATES AND TERRITORIES.- COMMISSIONER TO LOCATE WESTERN AND NORTHERN BOUNDARY OF PENN- SYLVANIA. GEOGRAPHER OF THE UNITED STATES.-WESTERN BOUNDARY OF NEW YORK.-FIRST ACTUAL MEASUREMENT OF NIAGARA FALLS.-SUR- VEY OF THE DISTRICT OF COLUMBIA AND WASHINGTON CITY-BOUN- DARY LINE BETWEEN THE UNITED STATES AND THE SPANISH POSSESSIONS. -SURVEYOR-GENERAL OF THE UNITED STATES.-LONGITUDE FROM WASH- INGTON. SELF-TAUGHT ASTRONOMER.-COMMISSIONER OF INTERNAL IM- PROVEMENTS OF PENNSYLVANIA.-NORTHERN BOUNDARY OF GEORGIA.— PROFESSOR OF MATHEMATICS IN THE MILITARY ACADEMY AT WEST POINT. ENGINEER ON ERIE CANAL.-ENGINEER OF CHAMPLAIN CANAL.-ENGINEER OF OHIO CANALS.-REPORT OF STATE COMMISSIONERS.-SURVEYOR FOR A CANAL IN THE STATE OF MAINE.-ENGINEER OF LOCATION OF THE CHESA- LAND SURVEYING.-FIRST WORK AS A CIVIL ENGINEER.-SURVEY OF THE MO- |