This item was an instrument used for measuring the intensity of a light source. It uses a light-sensing device that is calibrated to express intensity in a standard unit. Some optical elements such as lens etc. are also employed to incerase the sensitivity of the instrument.
HartmannThe fond contains Results of observations of the fixed stars made with the Meridian Circle at the Government Observatory , Madras
Pogson, Norman RobertThis item was a stellar object requires two coordinates to locate it on the sky, as the sky is a two-dimensional plane. One of these coordinates known as declination. This is similar to the two co-ordinates viz. latitude and longitude, defining a point on the surface of the earth. The transit circle is an instrument used to determine the declination of stellar onjects. It consists of a circular scale kept perpendicular to the rotating axis of a telescope tube.
Airy, George BiddellThe item is a 6 inch transit circle. The transit circle is an instrument used to determine the declination of stellar onjects. It consists of a circular scale kept perpendicular to the rotating axis of a telescope tube.
Madras Observatory