Building 51 | Building 51 | single victorian era c. 1870’s gargantuan exterior post-fire osborne and adams building window keystone comprised of patented artificial stone
11772
portfolio_page-template-default,single,single-portfolio_page,postid-11772,cstmsrch_elision,ajax_fade,page_not_loaded,,qode-child-theme-ver-1.0.0,qode-theme-ver-3.5,wpb-js-composer js-comp-ver-5.1.1,vc_responsive
 

single victorian era c. 1870’s gargantuan exterior post-fire osborne and adams building window keystone comprised of patented artificial stone

51-23726-16

Category

Chicago Buildings

About This Item

all original and largely intact early 1870’s artificial stone fragment or oversized keystone element salvaged from the post-fire osborne & adams commercial loft building on lake street. the light grey wedge of cast stone features simple design elements and a relatively smooth surface. the stone was formulated and patented by aaron frear in chicago on march 29, 1870, and is comprised of an aqueous saccharine solution of litharge, particles of silex, alumina, calcium and minerals, and metallic oxides. artificial stone was one of several materials relied upon as an alternate material in post-fire building. also termed “cast” or “concrete” stone, it is a synthetic product that was used mainly during the 18th and 19th centuries to imitate natural building stones. an aggregate of water, natural cement, lime, sand, and/or various binding agents, the concrete mixtures could be incorporated in construction as molded shapes and intricate decorative elements or as plain blocks. with various basic mixtures, production processes, and methods of finishing, cast stone could be employed to imitate a wide array of natural materials. a light cement matrix with crushed marble could replicate limestone, while a mix of marble and small amounts of melting slag would give the effect of white granite; the addition of masonry pigments could imitate variegated sandstone. some of the earliest formulas were created in britain, with coade stone produced from 1769-1833, and a patent process in 1844 of a formula by frederick ransome. additionally, coignet stone and frear stone (created by chicagoan george frear) were patented several years prior to the great fire of chicago. artificial stone gained traction in the period after the civil war and preceding the fire of 1871, becoming a commonly accepted, economical substitute for natural materials. the use of cast stone grew rapidly into the early twentieth century, sometimes comprising the only exterior facing material for a building, but more often as trim on a rock-faced stone or brick wall. certain types of artificial stone were made to be practically non-porous, and thus especially resistant to corrosion from salty or polluted air. victorian-era buildings constructed with artificial stone are well represented by structures like the osborne & adams leather company building at 209 west lake street, built 1872-1874. william henri adams was born in 1840 in chicago, and entered the leather store of osborn & adams, of which his father, william hanford adams, was a member, where he worked as clerk and bookkeeper til 1870, when he was admitted to membership in the firm which was burned out in the great fire of october, 1871. mr. osborn’s wife died during the fire, and he subsequently retired from the firm, with the business carried on by william h. adams & son until 1873 when the firm wound up its business and mr. adams went into the saddlery hardware business in which he continued for the next 7-8 years. in 1882 he commenced the practice of architecture and opened an office in the bryan block, removing from there to the chamber of commerce building, then to the rookery building, of which he was one of the first tenants. within chicago’s loop neighborhood, the commercial buildings erected in the aftermath of the great chicago fire are a rare remnant of unprecedented approaches to construction, in which commercial architecture facilitated the birth of the multi-story skyscraper in the early to mid 1880’s. most commercial loft buildings contained a different manufacturer on each floor, and were typically italianate in style. within a decade or two of being built, the 4 and 5 story victorian-era buildings quickly fell out of style and were demolished to make way for larger, more spacious buildings utilizing a steel and skeleton framework method.