Map of Clara Township
- Media Type:
- Item Type:
- Plan for the Township of Clara
- Early surveyors, like William E. Logan, used Rochon micrometer telescopes and targets (disk on a calibrated pole) to measure distance. Each microscope had a different calibration and therefore a different range. The instruments were calibrated against a distance measured with a surveyors chain (also known as Gunter’s chain). One chain had 100 links and was 66 feet (about 20 meters) or 22 yards long.
William E. Logan (2007). 1845 Survey of the Upper Ottawa Valley. Mercury Series History Paper 54. Charles H. Smith and Ian Dyck (eds.). Gatineau, Quebec: Canadian Museum of Civilization Corporation.
surveyor’s chain. (2010). In Encyclopædia Britannica. Retrieved April 14, 2010, from Encyclopædia Britannica Online: http://www.britannica.com/EBchecked/topic/575448/surveyors-chain
- Date of Original:
- Map Scale:
- 40 chains to an inch
- Township Collection
- Language of Item:
- Geographic Coverage:
- Creative Commons licence:
- [more details]
- Copyright Statement:
- Copyright status unknown. Responsibility for determining the copyright status and any use rests exclusively with the user.
Head, Clara and Maria Public Library