Lesson plan
Sharp Scale
The Sharp Scale was devised by Henrietta Sharp Cockrell as an objective and scientific way to measure the opacity of paper, particularly of manuscript folios, 'in the field' without specialized equipment. A practical application of the technique could be done in a museum or library setting. To apply the method, the folio is first held at a distance of 15 cm from a 60 watt light source (such as an unshaded table lamp). A dowel (or pencil) is held behind and against it, creating a silhouette. Folios are then added until the outline of the pencil is no longer visible. The number of the folios needed to obscure the silhouette of the pencil is recorded.
Article summary
The Sharp Scale was devised by Henrietta Sharp Cockrell as an objective and scientific way to measure the opacity of paper, particularly of manuscript folios, 'in the field' without specialized equipment. A practical application of the technique could be done in a museum or library setting. To apply the method, the folio is first held at a distance of 15 cm from a 60 watt light source (such as an unshaded table lamp). A dowel (or pencil) is held behind and against it, creating a silhouette. Folios are then added until the outline of the pencil is no longer visible. The number of the folios needed to obscure the silhouette of the pencil is recorded.
Key claims
No claims recorded.
Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
- Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
- If two sources disagreed about one of these facts, what would you need in order to trust one over the other?
Bibliography
No sources recorded.
Key claims and bibliography are generated from the same tracked claims and sources as the article page.