Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    The use of the collimator with an altitude and azimuth instrument
    From: Joel Jacobs
    Date: 2004 Feb 3, 07:45 -0500
    FYI, Someone might find this interesting. It needs to be tracked to its origin
  • Observatory, Astronomical: Part I; 14 pages, 6 plates of illus. Price 2.00 {Item No.20414} [Includes: Introduction, Meridian instrument rooms: The transit, The mural meridian circle, The transit circle, The repeating circle, The equatorial, Portable observatories, Altitude and azimuth instrument, Repeating circle (table)] [References part III of this article]
  • Observatory, Astronomical: Part II: On the proper manner of comparing chronometers and other time-keepers; 9 pages Price 1.00 {Item No.20415} [Includes: A.I. General rule, A.II. To compare a solar half seconds chronometer with a sidereal clock, by coincidence of beats A.III. To compare a pocket chronometer beating five times in two seconds, and going mean solar time nearly, with a sidereal clock, by coincidence of beats. I. To adjust a portable transit instrument, II. To determine the latitude by the transit, III. To determine the latitude with the altitude and azimuth instrument, IV. To determine the sidereal time in a place whose latitude is known, by observation with the altitude and azimuth instrument, V. To determine the latitude and the sidereal time in a place where neither of them is known, by observations with the altitude and azimuth instrument, VI. Observation of equal altitude not recommended for use, VII. General remarks on the rise of the sun instead of a star, in any of the preceding observations]
  • Observatory, Astronomical: Part III: Observatory, Portable; 4 pages, 7 plates of illus. Price 2.00 {Item No.20416} [Construction plans for a portable observatory]
  • Observatory, Astronomical: Part IV: Description of the Principle Astronomical Instruments; 19 pages, 6 illus. Price 2.00 {Item No.20417} [Includes: I. Hadley's sextant: To examine the error arising from the imperfection of the dark glasses, To adjust the horizon glass, To examine if the index glass be perpendicular to the plane of the instrument, To adjust the line of collimation, To determine the index error, Note. 2. Troughton's reflecting circle: Directions for observing with Troughton's reflecting circle. 3. The Transit Instrument: To make the axis horizontal, To adjust the line of collimation in azimuth, To adjust the transit to the meridian, Example, Method of observing with the transit, Use of the portable transit. 4. The portable Altitude and azimuth instruments: Introduction, Adjustments: Adjustments of the vertical axis, Adjustment of the horizontal axis, Adjustment of the circle to its reading microscopes, Adjustment of collimation in azimuth, Adjustment of collimation to altitude, Use of the altitude and azimuth instrument. 5. The Reading Microscope: Adjustments of the reading microscope. 6. The Collimator: The use of the collimator with an altitude and azimuth instrument, Example]
  • Note. This entire section on 'Observatory, Astronomical' is available: 44 pages, 6 figures and 14 plates of illus. Price 7.00 {Item No.20418}
    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site