Lunars from 1888 Bowditch

Today, Friday 25 Jan 2002 at 16:27:09 PST I scanned some pages from the 1888 edition of Nathaniel Bowditch's American Practical Navigator.
I believe this to be legal because it is an old government document that does not claim any copyright on the title page or its reverse, and it is over 100 years old as well.
I was going to scan the title page, but in the process of scanning these pages the binding of this very old and rare book broke. It nearly broke my heart as well. It only will have "died in vain" if we cannot figure out the lunars which were so dear to Mr. Bowditch.

These pages were scanned in using a Canon flatbed scanner and Adobe Photoshop 6.0 on an Apple Macintosh PowerBook G3 running Mac OS 9.2.2. They were scanned in at 300 dots per inch and were rendered as grayscale JPGs. They are all 928 x 1392 pixels in pixel dimension, and each is between 150-300 KB in size on disk. The 11 images total 2.18 MB, the smallest that I could make the images still readable. They should be OCR'd and turned into a HTML file.

If you are using IE 6.0 on the PC you will see the images scrunched small. Make sure to click in the lower left corner of the image to get the zoom button to show the images full size. Prepare to scroll around a bunch to read the documents. There is no way around this. It may be best to print them out.

Now for a brief comment on this material. The tables referred to on pages 133 through 141 are long and I have not reproduced most of them. Lunars also depend upon special tables in the Nautical Almanac that no longer exist, so the information is not very useful, but, here are the pages...

Page 133 - Lunar distances
Page 134 - Lunar distances continued
Page 135 - General remarks on the taking of a lunar observation
Page 136 - To correct the lunar distance; The observation; Preparation of the data
Page 137 - Computation of the true distances; To find the Greenwich Time
Page 138 - Degree of dependence
Page 139 - Example
Page 140 - Method of taking a lunar observation with one observer
Page 141 - Three examples
Page 332 - Table 29 - Mean reduced refraction for Lunars
Page 333 - Table 30 - First correction to the lunar distance

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Created:  25 Jan 2002
Modified: 22 Mar 2002