Editing Microtome (section)

==History==
[[File:Cummings 1774 Microtome.jpg|thumb|150px|A diagram of a microtome drawn by Cummings in 1770<ref name="Hill_1770"/>]]
In the beginnings of [[light microscope]] development, sections from plants and animals were manually prepared using razor blades. It was found that to observe the structure of the specimen under observation it was important to make clean reproducible cuts on the order of 100&nbsp;μm, through which light can be transmitted. This allowed for the observation of samples using light microscopes in a transmission mode.

One of the first devices for the preparation of such cuts was invented in 1770 by George Adams, Jr. (1750–1795) and further developed by [[Alexander Cummings]].<ref>{{Cite book
  | last = Quekett
  | first = John
  | title = A Practical Treatise on the use of the Microscope
  | publisher = Hippolyte Bailliere
  | year = 1848
  | location = London
  | pages = [https://archive.org/details/practicaltreatis00quekuoft/page/306 306], Chapter XII (Microtomes and Microtome Knives)
  | url = https://archive.org/details/practicaltreatis00quekuoft
  }}</ref> The device was hand operated, and the sample held in a cylinder and sections created from the top of the sample using a hand crank.<ref name="Hill_1770">{{Cite book
  | last = Hill
  | first = John
  | title = The Construction of Timber, from its early growth; Explained by Microscope, and proven from Experiments, in a great Variety of Kinds.
  | publisher =The author
  | year = 1770
  | location = London
  | pages = [https://archive.org/details/constructiontim00hillgoog/page/n10 5]–11, Plate I
  | url = https://archive.org/details/constructiontim00hillgoog}}</ref><ref name="Anonymous_1910">{{Cite journal
  | last = Anonymous
  | title = An eighteenth century Microtome
  | journal = Journal of the Royal Microscopical Society
  | pages = 779–782
  | publisher = The Royal Microscopical Society
  | location = Oxford, England
  | year = 1910
  | title-link = :File:Anonymous 1910 An Eighteenth Century Microtome.pdf
  }}</ref>

In 1835, Andrew Prichard developed a table based model which allowed for the vibration to be isolated by affixing the device to the table, separating the operator from the knife.<ref name="Gilbert Morgan Smith">Gilbert Morgan Smith: ''The Development of Botanical Microtechnique.'' In: ''Transactions of the American Microscopical Society'' 34, Nr. 2. 1915, S. 71–129, ([https://web.archive.org/web/20090704211541/http://scientificobjects.mpiwg-berlin.mpg.de/scientificobjects/dms/ResearchNetworkDocuments/basicdocuments/V1_Smith--technique1915/V1_Smith,%20technique1915.pdf PDF-Version of the article)] {{JSTOR|3221940}} {{doi|10.2307/3221940}} {{free access}}</ref>

Occasionally, attribution for the invention of the microtome is given to the anatomist [[Wilhelm His, Sr.]] (1865).<ref>{{Cite web| publisher= Encyclopædia Britannica|url= http://www.britannica.com/EBchecked/topic/266898/Wilhelm-His|title= Wilhelm His|series= Encyclopædia Britannica Online|access-date=24 March 2009}}</ref><ref>{{Cite journal
  | vauthors=Loukas M, Clarke P, Tubbs RS, Kapos T, Trotz M 
  | title = The His family and their contributions to cardiology
  | journal = International Journal of Cardiology
  | volume = 123
  | issue = 2
  | pages = 75–78
  | year = 2008
  | issn = 0167-5273
  | pmid = 17433467
  | doi = 10.1016/j.ijcard.2006.12.070
  }}</ref>
In his {{Lang|de|Beschreibung eines Mikrotoms}} (German for ''Description of a Microtome''), Wilhelm wrote:

{{quote|The apparatus has enabled a precision in work by which I can achieve sections that by hand I cannot possibly create. Namely it has enabled the possibility of achieving unbroken sections of objects in the course of research.}}

Other sources further attribute the development to a Czech physiologist [[Jan Evangelista Purkyně]].<ref>{{Cite web |url= http://encarta.msn.com/encyclopedia_761573144/histology.html |title= Histology |work= msn Encarta |access-date=18 March 2009|archive-url=https://web.archive.org/web/20090425234311/http://encarta.msn.com/encyclopedia_761573144/Histology.html |archive-date=25 April 2009 |url-status=dead}}</ref>  Several sources describe the Purkyne model as the first in practical use.<ref>Detlev Ganten: ''Handbuch der molekularen Medizin (Handbook of molecular medicine)'', Springer, {{ISBN|3-540-64552-7}}, ([https://books.google.com/books?id=DjwuzN4XvLMC Google-Books])</ref><ref>Werner Gerabek, Bernhard D. Haage, Gundolf Keil, Wolfgang Wegner (2005): ''Enzyklopädie Medizingeschichte'' (Encyclopaedia of medical history), Walter de Gruyter, {{ISBN|3-11-015714-4}}, ([https://books.google.com/books?id=LLoOUP-y54YC Google-Books])</ref>

The obscurities in the origins of the microtome are due to the fact that the first microtomes were simply cutting apparatuses, and the developmental phase of early devices is widely undocumented.

At the end of the 1800s, the development of very thin and consistently thin samples by microtomy, together with the selective staining of important cell components or molecules allowed for the visualisation of microscope details.<ref>{{Cite book|author=Ernst Mayr|title=''Die Entwicklung der biologischen Gedankenwelt.'' (The evolution of the biological thought )|publisher=Springer|year=2002|isbn=978-3-540-43213-5|url=https://books.google.com/books?id=Y_HvUDa4OqwC&pg=PA533}}</ref><ref>Werner Linß, Werner Linb, Jochen Fanghänel: ''Histologie: Zytologie, allgemeine Histologie, mikroskopische Anatomie.'' (Histology: Cytology, general Histology, microscopial anatomy) Walter de Gruyter, 1998, {{ISBN|3-11-014032-2}} ([https://books.google.com/books?id=S1HRxeGOQfMC&dq=Purkinjes+mikrotom&pg=PA1 Google-Books])</ref>

Today, the majority of microtomes are a knife-block design with a changeable knife, a specimen holder and an advancement mechanism. In most devices the cutting of the sample begins by moving the sample over the knife, where the advancement mechanism automatically moves forward such that the next cut for a chosen thickness can be made. The section thickness is controlled by an adjustment mechanism, allowing for precise control.