General Information

Serial #

1872-92 (Inv.)

Part Number

1

Total Parts

1

AKA

N/A

Patents

N/A

General Description

WOOD/ BRASS

Dimensions

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

Length

46.3 cm

Width

38.7 cm

Height

83.8 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Mathematics

Category

Models

Sub-Category

N/A

Manufacturer

AKA

DeLagrange

Country

France

State/Province

Unknown

City

Paris

Context

Country

Unknown

State/Province

Unknown

Period

Unknown

Canada

In 1872 the South Kensington Museum in London UK commissioned Fabre de Lagrange of Paris to make 45 mathematical models for their Education Collection. The Canada Science and Technology Museums Corporation obtaind 28 of them from the Science Museum in 1973 through a deaccession. They still have seventeen models from the original commission.

Function

USED AS VISUAL AID FOR TEACHING DESCRIPTIVE GEOMETRY OF ENGINEERING.

Technical

In this model two bars are pierced with holes at equal distances, the holes being connected by two different systems of strings.The surface, as well as the arrangement, is very nearly the same as the arrangement in Inv. 1872-9, but there are two paraboloids instead of one. As the movable bar swings round, one paraboloid opens out while the other closes up. If the bar is swung so as to be in the same plane, one system of strings describes a plane by parallel lines and the other by lines radiating from a point. If one bar is now turned so as to be end for end, we still get a plane, the set of parallel lines now passing through a point, while the set which previously passed through a point has now become parallel. The pair of paraboloids intersect in three right lines. There is also a fourth intersection on the "line at infinity."

Area Notes

Unknown

Details

Markings

S/N '1872-92'

Missing

GOOD, MOST STRINGS ARE MISSING

Finish

WOOD 'T'-SHAPED BOX: CROSS PT 17-1/2" X 3", STEM PT 12" X 3", BOTH 18" HIGH/ 'T'-SHAPED COVER WITH 16" LONG SLOT ON CROSS PART/ MOUNTED ON STEM PART OF COVER IS A BRASS FRAMEWORK SUPPORTING A 16" BRASS BAR 1-1/2" ABOVE THE SLOT/ A 16" BRASS BAR SWIVELLED TO FRAME/ UPRIGHT FRAME MAY BE ADJUSTED TO ANY ANGLE OVER THE BOTTOM BAR/ THREADS DESCEND FROM TOP BAR THROUGH THE BOTTOM ONE, AND INTO THE BOX/ THREADS ARE LEAD-WEIGHTED

Decoration

N/A