measuring engine
Date: 1940s-1950s
Inventory Number: 2005-1-0017
Classification: Measuring engine
Subject:
Maker: Mann Instrument Company (1920 - 1959)
User: Harvard College Observatory (founded 1839)
Cultural Region:
Place of Origin:
City of Use:
Dimensions:
50 x 79 x 79 cm (19 11/16 x 31 1/8 x 31 1/8 in.)
DescriptionMeasuring engine with a bed that moves in two dimensions and a magnifying viewer.
The bed is a hollow three-dimensional trapezoid made of black-enameled metal with an open top and four feet. At the right end of the bed is a brass wheel with a scale around the edge. Attached to that wheel coaxially is a second wheel, black with rounded edges, with a handle on the edge that is parallel to the axis of the wheels. A platform, whose length is perpendicular to the length of the bed, slides along the bed. A ruler on the front top edge of the bed allows the user to mark the exact position of the platform along the bed.
At the front end of the platform is another wheel, this one with a ridged edge, with a scale on it. Attached to the edge of the platform, right by the wheel, is a rectangular metal slab that hangs down from the edge. The slab has a hole in the shape of a square with a semicircle on one side. Around the hole are four horizontal slats.
On one side of the length of the platform is a ruler, along which another platform, square with a circular hole, slides. around this hole is a toothed wheel, on top of which is a metal circle with a square cut out of it. At each corner of the square is a clip with a screw attaching it to the metal circle. Along the side of the wheel are two verniers and a small toothed wheel interlocking with the larger wheel. That wheel is turned with a screw.
Hanging over the platform is an arm, attached to the rear of the bed, containing a microscope looking straight down to the plateholder. The arm tapers as it reachs the eyepiece assembly in front.
The bed is a hollow three-dimensional trapezoid made of black-enameled metal with an open top and four feet. At the right end of the bed is a brass wheel with a scale around the edge. Attached to that wheel coaxially is a second wheel, black with rounded edges, with a handle on the edge that is parallel to the axis of the wheels. A platform, whose length is perpendicular to the length of the bed, slides along the bed. A ruler on the front top edge of the bed allows the user to mark the exact position of the platform along the bed.
At the front end of the platform is another wheel, this one with a ridged edge, with a scale on it. Attached to the edge of the platform, right by the wheel, is a rectangular metal slab that hangs down from the edge. The slab has a hole in the shape of a square with a semicircle on one side. Around the hole are four horizontal slats.
On one side of the length of the platform is a ruler, along which another platform, square with a circular hole, slides. around this hole is a toothed wheel, on top of which is a metal circle with a square cut out of it. At each corner of the square is a clip with a screw attaching it to the metal circle. Along the side of the wheel are two verniers and a small toothed wheel interlocking with the larger wheel. That wheel is turned with a screw.
Hanging over the platform is an arm, attached to the rear of the bed, containing a microscope looking straight down to the plateholder. The arm tapers as it reachs the eyepiece assembly in front.
Inscribedstamped label: US Government Property -- 91760-090002
painted: 10005
painted: 10005
FunctionMeasuring engines are used for detailed measurements of features on photographic plates. One of its frequent uses (such as this particular one) is in astronomy to register the positions of stars.
They are also used in aerial photograpy, and in spectrography.
They are also used in aerial photograpy, and in spectrography.
ProvenanceHarvard College Observatory.