Daily Archives: 4/25/2005

Gutenberg Gem: How TO Make a Star Finder

A Star FinderA hacker’s project of old, perhaps as would have populated Make magazine had it existed in July of 1887:

The Project Gutenberg eBook of Scientific American Supplement, July 9, 1887

HOW TO MAKE A STAR FINDER.

Being all of wood, it is easily made by any one who can use a few tools, the only bit of lathe work necessary being the turned shoulder, K, of polar axis. A is the baseboard, 9 in. by 5 in., near each corner of which is inserted an ordinary wood screw, S S, for the purpose of leveling the base, to which two side pieces are nailed, having the angle, x, equal to the co-latitude of the place. On to these side pieces is fastened another board, on which is marked the hour circle, F. Through this board passes the lower end of the polar axis, having a shoulder turned up on it at K, and is secured by a wooden collar and pin underneath. On to the upper part of the polar axis is fastened the declination circle, C, 5½ in. diameter, made of ¼ in. baywood, having the outer rim of a thin compass card divided into degrees pasted on to it. The hour circle, F, is half of a similar card, with the hours painted underneath, and divided to 20 minutes. G is the hour index. D is a straight wooden pointer, 12 in. long, having a piece of brass tube, E, attached, and a small opening at J, into which is fixed the point of a common pin by which to set the pointer in declination. H is a nut to clamp pointer in position. By this simple toy affair I have often picked up the planet Venus at midday when visible to the naked eye.–T.R. Clapham in English Mechanic.

Weekend Experiment

Infrared PhotographEric’s exploration of digital infrared photography over on flutterby has urged me to try to take some more infrared photographs. Toward that end, I’ve created Experiments in Infrared Digital Photography in my brainwagon photo gallery. So far, there are only three images, all derived from a single shot of some plants that I did yesterday. I was experimenting with changing the result using gimp. Let me know what you think.