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Papers on Transit Circle I, 1878 - 1923

 File
Reference Code: GBR/0180/RGO 7/31

Scope and Contents

Report by H.H. Turner on the inclination of the horizontal wire of the transit circle, 24 November 1890.

Fifteen tables, one for each year, showing the monthly inclination of the horizontal wire of the transit circle, 1878-1892.

Correspondence on the loan of an instrument from the City and Guilds Engineering College to determine the flexure of the transit circle, 1915.

Correspondence with Troughton and Simms and with H.H. Turner concerning the difference between observations made direct and those made by reflection, and the possibility of the difference being caused by defective fitting of the object glass in the transit circle, 1894-1895.

Correspondence with Troughton and Simms regarding maintenance and repairs to the transit circle and some minor adjustments to correct faults, 1902-1923. There is also a report from T. Gray of Cooke, Troughton and Simms Ltd on 'The 8" Transit Circle faults', and full size blueprints of proposed alterations to the anti-friction rollers of the transit circle, dated October 1923.

Calculations to determine the inclination of the horizontal wire of the transit circle, 1888.

Correspondence with Troughton and Simms and members of the Royal Observatory staff on illuminating the microscopes of the transit circle, 1888.

Tables of readings for various collimators and tables showing the differences in their readings, 1886-1888.

Comparison tables of thermometer readings from the Astronomical Department and thermometer readings from standard thermometers, 1889.

Correspondence on the fitting of a new reflector to the Bohnenberger eyepiece, 1889.

Notes and tables on the following subjects, 1884-1889: 1. Residual temperature correction to north polar distance; 2. North polar distances of stars observed in different months; 3. Variations of the nadir; and 4. Diurnal variations of the level error.

Diurnal variations of the level and altazimuth, and tables and notes on amalgamated mercury trough experiments, 1884.

Correspondence with Troughton and Simms and notes and tables on the following subjects, 1888-1890: 1. Intervals of wires, 1888; 2. The difference between the exterior thermometer and the Magnetical and Meteorological Department standard thermometer; 3. The examination of 2D micrometer slips; 4. The differences of observation of collimators; 5. The mercury trough; and 6. Correspondence with Dr Spitts on the drilling of screen holes.

'Intervals between wires N + T and T + Z and N + Z' and notes on the alteration of level and altazimuth error of the transit circle, 1890.

Correspondence with James Simms on the polishing of the transit circle object glass and the new arrangement of the eyepiece, 1891.

Notes on the following subjects, 1890-1891: 1. Right ascension and zenith distance micrometer screws; 2. Number of transit wire; 3. Arrangements of transit webs in the transit circle; 4. Intervals of wires in the transit circle by means of the right ascension micrometer; and 5. Intervals of eye and ear wires, observations made on north collimation.

Differences of the exterior thermometers compared with the front court and magnetical and meteorological standard thermometer, 1891.

Result of the comparison of thermometers of the Astronomical Department with the standard, 1892.

Transit circle north polar distance observations of 11 November 1891.

Difference of readings for coincidence of wire of the north collimator with the corresponding wire of the south collimator through the tube of the transit circle with the instrument raised, from observations made during the year 1890, and the same table for 1891.

Error of passage of the Sun's diameter, 1885-1886.

Errors of the Sun's horizontal diameter, 1887-1888.

Errors of sidereal time of the passage of the Sun's diameter, 1889.

Error of the passage of the Sun's diameter, 1890.

Errors of horizontal diameters of the Sun, 1891-1892.

Errors of vertical diameters of the Sun, 1891-1892.

Notes and tables on the following subjects, 1891: 1. Intervals of wires of the transit circle; 2. Measures of the south collimator; 3. Measures of the south collimator; 4. Mean readings of the right ascension micrometer for altazimuth stars; 5. Intervals of wires I-X; 6. Intervals of wires II-IX; and 7. Table of the values of parts of a revolution of the right ascension micrometer.

Tables and rough notes on observations on the north collimator to determine the intervals of the eye and ear transit wires of the transit circle, 1891.

Notes on the following subjects, 1891: 1. Intervals of wires I-X; 2. Intervals of wires II-IX; 3. Measures on collimators to determine intervals of galvanic wires; and 4. Computations of the value of one revolution of the right ascension micrometer.

Figures showing the excess of the readings of the courtyard thermometer over the exterior thermometer at observations of the Sun during 1890.

Errors of the transit circle microscope screws.

Dimensions of the mercury trough of the transit circle, 13 December 1892.

Notes on the flexure of the transit circle, 1892.

Table showing observations of wire 'R' from 1 January 1893.

Notes to staff giving instructions for the use of instruments and orders concerning observations, 1887.



































































Dates

  • 1878 - 1923

Conditions Governing Access

Unless restrictions apply, the collection is open for consultation by researchers using the Manuscripts Reading Room at Cambridge University Library. For further details on conditions governing access please contact mss@lib.cam.ac.uk. Information about opening hours and obtaining a Cambridge University Library reader's ticket is available from the Library's website (www.lib.cam.ac.uk).

Extent

1 bundle(s) (1 bundle)

Language of Materials

English

Former / Other Reference

C1

Finding aid date

2006-03-30 10:40:17+00:00

Includes index.

Creator

Repository Details

Part of the Cambridge University Library Repository

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