Recent content by Harlan

A recent article in Smithsonian magazine about knitting geometric forms stimulated the following question: In the above, knitted Moebius strip, there are areas where the material is twisted (seen in front) and areas where the material is flatter/less twisted (seen in back). So far as I can...

Yes, the focus knob still works, and it is a refractor, so no mirrors.

OK - Here's a challenge. Our school has a theodolite; its telescope worked in the past. Now it suddenly won't focus beyond 7', though it gives a great image of objects between roughly 3'-7' away. The focus knob seems to move freely. My thought is that the eyepiece optics somehow got...