Description:
- Object ID: ALSA 2008.14.01
- Made by: Made In U.S.A. By American Paulin Systems, Los Angeles, California
- Model: M-2
- Serial Number:NS1201K
- Date Made: Unknown, circa 1920s to 1940s.
- Approximate size: 17.5 cm (diameter) X 9 cm (h)
- Accessories: Orange wooden box to house the two altimeters and an Altimetry Manual.
- Condition: excellent
Commentary:
This altimeter is one of a pair in the collection. They were owned by Harold Brown, ALS #156 of H.W. Brown & Company, predecessor of the company Brown Okamura & Associates Ltd. They were used to obtain topographic data for irrigation projects in the Bow River Irrigation District expansion in Southern Alberta in the 1950s.
Dave Williams, ALS (Ret.) describes the process:
“To obtain more reliable data than by using the altimeters independently, one altimeter was left on a place of known elevation (the base elevation) with reading taken at set time intervals. In the field, the time was recorded when each elevation was taken with the other altimeter. At the end of each day, the time of the elevation recorded in the field was compared to the reading on the base altimeter so a correction to the field data could be made. Using this method, any change in barometric pressure through the day was compensated for.”
“The elevations obtained by these altimeters were used to prepare contour plans of quarter sections to determine the extent of area that could be irrigated by flood irrigation methods. For areas that could be irrigated more precise data was obtained by spirit levels so the area could be mapped more accurately.”
Source of Object: Donated by Dave Williams ALS (Ret’d)
Notes: Second altimeter ALSA 2008.14.02.
References: Visit article The “Vagaries of that Instrument” – The Altimeter for more information.
Description by: Updated by Ed Titanich, September 27, 2024.