Editing Washington Monument (section)

====Resumption====
[[File:Washington Monument - Setting the capstone - Harper's Weekly.png|thumb|upright=1|P. H. McLaughlin setting the aluminum apex with Thomas Lincoln Casey (hands up)]]
[[File:View of the uncompleted Washington Monument, taken from the roof of the Main building of the Department of... - NARA - 516531.jpg|thumb|upright=1|Washington Monument nears completion around 1884]]
Construction resumed in 1879 under the direction of Lieutenant Colonel [[Thomas Lincoln Casey Sr.|Thomas Lincoln Casey]] of the [[United States Army Corps of Engineers]]. Casey redesigned the foundation, strengthening it so it could support a structure that ultimately weighed more than 40,000 tons ({{convert|40,000|ST|t|disp=out|abbr=off}}). The first stone atop the unfinished stump was laid on August 7, 1880, in a small ceremony attended by President [[Rutherford B. Hayes]], Casey and a few others. The president placed a small coin on which he had scratched his initials and the date in the bed of wet cement at the {{convert|150|foot|m|adj=on}} level before the first stone was laid on top of it.<ref name=Torres/>{{rp|76}} Casey found 92 memorial stones ("presented stones") already inlaid into the interior walls of the first phase of construction. Before construction continued he temporarily removed eight stones at the {{convert|150|foot|m|adj=on}} level so that the walls at that level could be sloped outward, producing thinner second-phase walls. He inserted those stones and most of the remaining memorial stones stored in the lapidarium into the interior walls during 1885–1889.<ref name=Jacob/>{{rp|11–17}} The bottom third of the monument is a slightly lighter shade than the rest of the construction because the marble was obtained from different quarries.<ref>{{cite web | url=http://www.nps.gov/nr/travel/wash/dc72.htm | title=Washington Monument | work=National Park Service | access-date=March 10, 2015 | quote=The walls of the monument range in thickness from 15' at the base to 18' at the upper shaft. They are composed primarily of white marble blocks from Maryland with a few from Massachusetts, underlain by Maryland blue gneiss and Maine granite. A slight color change is perceptible at the 150' level near where construction slowed in 1854.}}</ref>

The building of the monument proceeded quickly after Congress had provided sufficient funding. In four years, it was completed, with the 100-ounce (2.83&nbsp;kg) aluminum apex/lightning-rod being put in place on December 6, 1884.<ref name="reeves413"/> The apex was the largest single piece of aluminum cast at the time, when aluminum commanded a price comparable to silver.<ref name=Binczewski>{{cite journal|author = George J. Binczewski|title = The Point of a Monument: A History of the Aluminum Cap of the Washington Monument|journal = JOM|volume = 47|issue = 11|pages = 20–25|year = 1995|url = http://www.tms.org/pubs/journals/JOM/9511/Binczewski-9511.html|doi=10.1007/bf03221302|bibcode = 1995JOM....47k..20B|s2cid = 111724924}}</ref> Two years later, the [[Hall–Héroult process]] made aluminum easier to produce and the price of aluminum plummeted, though it should have provided a lustrous, non-rusting apex.{{efn-ua |name=rust |The large gold-plated copper band added to the aluminum apex in 1885 discolored or damaged the surface of the aluminum so much that most of its inscriptions are no longer legible – see [[#Aluminum apex|Aluminum apex]].}}<ref>{{cite web |url = http://portal.acs.org/portal/PublicWebSite/education/whatischemistry/landmarks/aluminumprocess/index.htm |archive-url = https://archive.today/20130223151952/http://portal.acs.org/portal/PublicWebSite/education/whatischemistry/landmarks/aluminumprocess/index.htm |url-status = dead |archive-date = February 23, 2013 |title = Hall Process: Production and Commercialization of Aluminum |publisher = American Chemical Society |work = National Historic Chemical Landmarks |access-date = March 25, 2013 }}</ref> The monument opened to the public on October 9, 1888.<ref>[http://www.cr.nps.gov/nr/travel/wash/dc72.htm "Washington Monument"] {{webarchive |url=https://web.archive.org/web/20141227003638/http://www.cr.nps.gov/nr/travel/wash/dc72.htm |date=December 27, 2014 }}. ''Teaching with Historic Places''. National Park Service. Retrieved October 15, 2006.</ref>