Alexander McMillan Welch (1869-1943) was a New York City based architect who practiced independently and as a member of Welch, Smith & Provot. His firm was best known for designing New York City townhouses in the Beaux-Arts style. The collection includes 1,641 architectural drawings, 196 student drawings, 14 student notebooks, 99 loose photographs and 3 photo albums of project photography, project specifications and files, and some professional ephemera.

Correspondence, manuscripts, documents, photographs, and memorabilia of Helen May MacLachlan. There are 570 letters from John Masefield and his wife to James Alexander MacLachlan, his wife Mary, and their children Howard James and Helen, 1916-1966, autograph poetry manuscripts, drawings, clippings, and 43 books presented by Masefield to Helen MacLachlan. Also, correspondence about the Theodore Roosevelt Association from Horace Marden Albright, Ethel Roosevelt Derby, Hermann Hagedorn, and others as well as correspondence from personal friends; and photographs of the MacLachlan family and friends.

Architectural drawings and specifications for Codman's projects, circa 1890s-1930s, including the Martha Codman house in Washington, D.C.; alterations for Edith Wharton and her husband at their three residences, the Mount in Lenox, Mass., Land's End in Newport, R.I., and their Park Avenue home in New York City; work for the Thayer family of Boston, Mass., specifically Nathaniel Thayer's three homes in Boston, Lancaster, Mass., and Newport, R.I. ("Edgemere"), Bernard Thayer's Beacon Hill houyse in Boston, and Eugene Van Rensselaer Thayer's two houses in Boston and Lancaster, Mass.; the Lucy Dahlgren house in New York City; the Archer M. Huntington house on Fifth Avenue in New York City; interior design for John D. Rockefeller in his house "Kykuit" at Pocantico Hills, N.Y.; interior design work for the Vanderbilt family including Cornelius Vanderbilt's "Breakers" at Newport, R.I. and Frederick William Vanderbilt's mansion in Hyde Park, N.Y. and his house on Fifth Avenue in New York City; Oliver Ames' mansion at Pride's Crossing, Beverly, Mass., and his house in Boston; and interior decoration and alterations for Codman's own homes in Newport, R.I. and Roslyn, N.Y. and his villa in France, "La Leopolda", at Villefranche-sur-Mer. Also, lists, descriptions, and postcards of French chateaux, with related correspondence, circa 1900s-1930s, relating to Codman's bibliography on the chateaux of France; and miscellaneous lists of houses in England and France, correspondence, and printed material.

The diary is a detailed account of Abbott's trip from Sydney, Australia to the Philippines, Hong Kong, Macao, China and Japan. There are numerous pen-and-ink sketches of landscape, architecture, historical sites, and inhabitants, and maps, some in water color. Pasted in the volume are memorabilia such as menus, hotel brochures, postcards, photographs, clippings, calling cards, etc. Of special interest are his accounts of the various native Christian communities he visited. Following the text there is a name index. In addition to the volume there are some related letters, documents, memorabilia and published maps.

Business and project records from the non-profit industrial design and architecture firm and its successor, the for-profit REDE Corp. Collection includes correspondence, reports, manuscripts, photographs, drawings, project files, posters, audiovisual material, more.

This collection contains professional and personal writings, published papers, correspondence, photographs, architectural records, student work, and research materials related to the academic and architectural practice of Talbot Faulkner Hamlin.

The Benson John Lossing Collection is an assortment of correspondence, drawings, writings, and memorabilia relating to the 19th century historian, illustrator, and editor of The American Historical Review (1813-1891). Predominantly correspondence, the collection centers around Lossing's information gathering for his popularizations of American history, while it also illuminates the early publishing industry in the United States.

Papers of the American industrial designer. Business records (1931-1964) pertaining to clients including American Cyanamid Corporation, Casein Company of America, Cornwall Corporation, and General Electric Company; architectural drawings, articles, lectures, book manuscripts, photographs, consumer and trade surveys, 1943-1959; clay, plaster, and paper models; and scrapbooks of clippings.