Report of the Commissioner of Patents for the year .. (1849)
United States. Patent Office · Washington : Office of Printers to House of Reps. · leaf 372
erence indicates the depression of x below a. If to preserve the inclination it becomes necessary to follow a very tor- tuous line, it may be avoided by sinking the ditch at certain points, and raising it by means of embankments at others. If the inclination between the points a and x is too great…
United States. Patent Office · Patents · Agriculture
Internet Archive · Smithsonian Libraries · Public domain (published before 1931). Free to use for anything.
![An illustration from Rudiments of the art of building : represented in five sections [...] for the use of architects, builders, draghtsmen, machinists, engineers and mechanics (1853)](https://img.insideoutlibrary.com/img/200/ia-rudimentsofartof00bull-127-63.webp)
