The cast iron version ofP-72110.  The Monadnock Block in Chicago was originally designed in 1889 to function as one building but could be 4 separate buildings if the Brooks family so desired.  The northern section was completed in 1891 to designs by Burnham & Root, and was comprised of the Monadnock and Kearsage sections, which had M and K doorknobs.  This is the tallest masonry structure in the United States.  In 1893 the southern half of the building completed by architects Holabird & Roche with steel frame construction.  The Wachusett and Kathadin sections have doorknobs with K and W. Click on each photo below to view additional images and information.