Editing Uniformitarianism (section)

===18th century===

[[Image:Siccar point SE cliff.jpg|thumb|Cliff at the east of [[Siccar Point]] in Berwickshire, showing the gently tilting red sandstone layers above vertically tilted greywacke rocks.]]

[[Abraham Gottlob Werner]] (1749–1817) proposed [[Neptunism]], where [[stratum|strata]] represented deposits from shrinking seas [[Precipitation (chemistry)|precipitated]] onto primordial rocks such as [[granite]]. In 1785 [[James Hutton]] proposed an opposing, self-maintaining infinite cycle based on natural history and not on the [[Bible|Biblical]] account.<ref>{{Harvnb|Bowler|2003|pp=57–62}}</ref><ref>{{cite web|author=Hutton, J. |date=1785 |url=http://www.uwmc.uwc.edu/geography/hutton/Abstract-facsimile/abstract1.htm |title=Abstract, The System of the Earth, Its Duration and Stability |quote=As ''it is not in human record, but in natural history'', that we are to look for the means of ascertaining what has already been, it is here proposed to examine the appearances of the earth, in order to be informed of operations which have been transacted in time past.  It is thus that, from principles of natural philosophy, ''we may arrive at some knowledge'' of order and system in the economy of this globe, and may ''form a rational opinion'' with regard to the course of nature, or to events which are in time to happen. |url-status=dead |archive-url=https://web.archive.org/web/20080907225227/http://www.uwmc.uwc.edu/geography/hutton/Abstract-facsimile/abstract1.htm |archive-date=2008-09-07 }}</ref>
{{Quote|The solid parts of the present land appear in general, to have been composed of the productions of the sea, and of other materials similar to those now found upon the shores. Hence we find a reason to conclude:<br />
:1st, That the land on which we rest is not simple and original, but that it is a composition, and had been formed by the operation of second causes.
:2nd, That before the present land was made, there had subsisted a world composed of sea and land, in which were tides and currents, with such operations at the bottom of the sea as now take place. And,
:Lastly, That while the present land was forming at the bottom of the ocean, the former land maintained plants and animals; at least the sea was then inhabited by animals, in a similar manner as it is at present.
Hence we are led to conclude, that the greater part of our land, if not the whole had been produced by operations natural to this globe; but that in order to make this land a permanent body, resisting the operations of the waters, two things had been required;<br />
:1st, The consolidation of masses formed by collections of loose or incoherent materials;
:2ndly, The elevation of those consolidated masses from the bottom of the sea, the place where they were collected, to the stations in which they now remain above the level of the ocean.<ref>[http://www.uwmc.uwc.edu/geography/hutton/Abstract-facsimile/abstract1.htm ''Concerning the System of the Earth''] {{webarchive|url=https://web.archive.org/web/20080907225227/http://www.uwmc.uwc.edu/geography/hutton/Abstract-facsimile/abstract1.htm |date=2008-09-07 }} abstract, as read by [[James Hutton]] at a meeting of the [[Royal Society of Edinburgh]] on 4 July 1785, printed and circulated privately.</ref>}}

Hutton then sought evidence to support his idea that there must have been repeated cycles, each involving [[Deposition (sediment)|deposition]] on the [[seabed]], uplift with tilting and [[erosion]], and then moving undersea again for further layers to be deposited. At [[Glen Tilt]] in the [[Cairngorms|Cairngorm mountains]] he found granite penetrating [[metamorphic rock|metamorphic]] [[schist]]s, in a way which indicated to him that the presumed primordial rock had been [[molten]] after the strata had formed.<ref name="Macfarlane">{{cite news|url=http://findarticles.com/p/articles/mi_qa3724/is_200309/ai_n9253355 |archive-url=https://web.archive.org/web/20071101110825/http://findarticles.com/p/articles/mi_qa3724/is_200309/ai_n9253355 |url-status=dead |archive-date=1 November 2007 |title=Glimpses into the abyss of time |author=Robert Macfarlane |work=[[The Spectator]] |date=13 September 2003 |quote=Hutton possessed an instinctive ability to reverse physical processes – to read landscapes backwards, as it were.  Fingering the white quartz which seamed the grey granite boulders in a Scottish glen, for instance, he understood the confrontation that had once occurred between the two types of rock, and he perceived how, under fantastic pressure, the molten quartz had forced its way into the weaknesses in the mother granite.}} Review of Repcheck's ''The Man Who Found Time''</ref><ref name=tilt>{{cite web|url= http://www.scottishgeology.com/outandabout/classic_sites/locations/glen_tilt.html|archive-url= https://archive.today/20060616043401/http://www.scottishgeology.com/outandabout/classic_sites/locations/glen_tilt.html|url-status= dead|archive-date= 2006-06-16|title= Scottish Geology – Glen Tilt}}</ref> He had read about [[unconformity|angular unconformities]] as interpreted by Neptunists, and found an [[Hutton's Unconformity|unconformity]] at [[Jedburgh]] where layers of [[greywacke]] in the lower layers of the cliff face have been tilted almost vertically before being eroded to form a level plane, under horizontal layers of [[Old Red Sandstone]].<ref name="Unconformity Jedburgh">{{cite web |url= http://www.jedburgh-online.org.uk/aroundjedburgh.asp |title= Jedburgh: Hutton's Unconformity |work= Jedburgh online |quote= Whilst visiting Allar's Mill on the Jed Water, Hutton was delighted to see horizontal bands of red sandstone lying 'unconformably' on top of near vertical and folded bands of rock. |url-status= dead |archive-url= https://web.archive.org/web/20090729030536/http://www.jedburgh-online.org.uk/aroundjedburgh.asp |archive-date= 2009-07-29 }}</ref> In the spring of 1788 he took a boat trip along the [[Berwickshire]] coast with [[John Playfair]] and the geologist [[Sir James Hall, 4th Baronet|Sir James Hall]], and found a dramatic unconformity showing the same sequence at [[Siccar Point]].<ref>{{Cite web|url= http://www.snh.org.uk/publications/on-line/geology/elothian_borders/hutton.asp|title= Hutton's Unconformity|url-status= dead|archive-url= https://web.archive.org/web/20150924104617/http://www.snh.org.uk/publications/on-line/geology/elothian_borders/hutton.asp|archive-date= 2015-09-24}}</ref> Playfair later recalled that "the mind seemed to grow giddy by looking so far into the abyss of time",<ref name="Playfair RSE">{{cite news|url=http://findarticles.com/p/articles/mi_m1134/is_5_108/ai_54830705 |archive-url=https://web.archive.org/web/20050107022523/http://www.findarticles.com/p/articles/mi_m1134/is_5_108/ai_54830705 |url-status=dead |archive-date=2005-01-07 |title=Hutton's Unconformity |author=John Playfair |work=Transactions of the [[Royal Society of Edinburgh]], vol. V, pt. III, 1805, quoted in [[Natural History (magazine)|Natural History]], June 1999 |year=1999 |author-link=John Playfair }}</ref> and Hutton concluded a 1788 paper he presented at the [[Royal Society of Edinburgh]], later rewritten as a book, with the phrase "we find no vestige of a beginning, no prospect of an end".<ref name="KS Thomson">{{cite journal |url= http://www.americanscientist.org/issues/id.3275,y.0,no.,content.true,page.2,css.print/issue.aspx |title= Vestiges of James Hutton |author= Keith Stewart Thomson |journal= American Scientist |volume= 89 |issue= 3 |page= 212 |date= May–June 2001 |doi= 10.1511/2001.3.212 |quote= It is ironic that Hutton, the man whose prose style is usually dismissed as unreadable, should have coined one of the most memorable, and indeed lyrical, sentences in all science: "(in geology) we find no vestige of a beginning,—no prospect of an end". In those simple words, Hutton framed a concept that no one had previously contemplated, that the rocks making up the earth today have not, after all, been here since Creation. |url-status= dead |archive-url= https://web.archive.org/web/20110611161755/http://www.americanscientist.org/issues/id.3275,y.0,no.,content.true,page.2,css.print/issue.aspx |archive-date= 2011-06-11 }}</ref>

Both Playfair and Hall wrote their own books on the theory, and for decades robust debate continued between Hutton's supporters and the Neptunists. [[Georges Cuvier]]'s [[history of paleontology|paleontological work]] in the 1790s, which established the reality of [[extinction]], explained this by local catastrophes, after which other fixed species repopulated the affected areas. In Britain, geologists adapted this idea into "[[Diluvium|diluvial theory]]" which proposed repeated worldwide annihilation and creation of new fixed species adapted to a changed environment, initially identifying the most recent catastrophe as the [[Deluge (mythology)|biblical flood]].<ref>
{{Harvnb|Bowler|2003|pp= 111–117}}
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