Somewhat repeating the previous post, go to the Library of Congress copyright site and read up on "fair use." You can also check if the original publisher is still in business. If not your chances of problems are pretty slim.
As to the technical question, the majority of these were probably shot with a "normal" lens. However, normal lenses for view cameras and medium format were somewhat wider than what we think of from 35mm normal. A 35mm lens on full-frame sensor or 24mm lens on APS will likely get you in the ballpark for most of your sites, though you may have to crop a bit to exactly match the view. (A lot of the old timers cropped pretty freely anyway - film was larger back then and not many photographers owned a large selection of lenses.)
"We paint with our brain, not with our hands" -- Michelangelo
Portrait, figure and fantasy photography at Silver Mirage Gallery:
|_F0A5334-Edit_small by Dester Wallaboo|
from Open Air Fashion Photography
|Old Harry's Rocks by John93Robertson|
from View from the top - Sea