General Information

Serial #

27

Part Number

1

Total Parts

1

AKA

N/A

Patents

N/A

General Description

metal casing with synthetic parts. Glass.

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

22.7 cm

Width

18.5 cm

Height

13.4 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Physics

Category

Geophysics

Sub-Category

N/A

Manufacturer

AKA

Lacoste Romberg

Country

United States of America

State/Province

Texas

City

Austin

Context

Country

Canada

State/Province

Unknown

Period

Unknown

Canada

Taken from Acquisition proposal: Quoting from the NRCan web site: http://www.geod.nrcan.gc.ca/aboutus/gravity/grvinsts_e.php The Geodetic Survey Division owns and operates two absolute gravity instruments, JILA-2, and the A-10. It also collaborates with the GSC in the operation of a second instrument, FG5-106. The JILA-2 was acquired in November, 1985 and FG5-106 in April 1993. The A-10 instrument was acquired in 2000. The JILA-2 has been upgraded four times since it's acquisition with new computer control, new lasers, GPS clock and ancillary equipment. These upgrades were necessary in order to make it more efficient, field worthy, lighter and easier to use. Instrument modifications and tests are essential for Canada to remain at the leading edge in gravimetry. Because of their high accuracy of a few parts per billion, the instruments are used to establish, strengthen and expand the Canadian Gravity Standardization Net. Large calibration ranges are also established for the purpose of calibrating the complement of relative gravimeters owned by the Gravity and Geodetic Section. Smaller calibration ranges are maintained for industry so that companies can evaluate and compare their instruments against the established standard. Examples are the small calibration ranges between Ottawa and Gananoque and between Orangeville and Collingwood. The absolute gravimeters participate on a regular basis in international campaigns and comparisons in order to maintain the high standards of accuracy required of these instruments. The two most recent comparisons were done at the Bureau International des Poids et Mesures in Sevres, France, in 2001, and at Boulder, Colorado, USA, in 1995. The BIPM comparisons for instance occur every four years. Comparisons at the Canadian Absolute Gravity Site (CAGS) have been carried out every year with some exceptions since 1988 with the National Oceanic and Atmospheric Administration (NOAA) under an MOU.

Function

Allowed the researchers to very accurately determine changes in the Earth and the Earth's place in space.

Technical

These items have all played a role in Canada's position at the leading edge of gravimetry. Obviously the leading edge of 30 years ago is no longer the leading edge so NRCan has upgraded its instruments on a regular basis.

Area Notes

Unknown

Details

Markings

Mfr's plate reads: "LACOSTE & ROMBERG, INC./ GRAVITY METER/ 27 [engraved]/ U.S. PATENTS/ 2293437/ 2377889/ MADE IN/ AUSTIN, TEXAS/ U.S.A."/ Black labels with white embossed print read: "HI-SEN" and "NULL"/ White meter reads: "DIRECT CURRENT/ MICROAMPERES/ SIMPSON"/ Handwritten in marker "25" and "1977"

Missing

N/A

Finish

Metal grey casing with black control, glass meter reading with white background. Red switches. Black labels with white embossed print. Silver metal handle on top.

Decoration

N/A