Ha ha! Was safety glass bullet proof? I worked out the g force once. I forget the answer now but it was terrific. If my balance weight came adrift it would be like a bullet. So as you can imagine it's pretty well fixed - bolted on in fact.
Looking back to the '30s, it really is incredible what TeKaDe achieved in constructing a (presumably) accurate 180-line mirror screw with the methods available at the time. The optical tolerances are very tight when you have a large number of lines. But then we also marvel at what Scophony achieved. The engineers of the 1930s were no dummies. And after all, precision engineering has long been needed for the likes of motor car and aircraft engines.
Looking back to the '30s, it really is incredible what TeKaDe achieved in constructing a (presumably) accurate 180-line mirror screw with the methods available at the time. The optical tolerances are very tight when you have a large number of lines. But then we also marvel at what Scophony achieved. The engineers of the 1930s were no dummies. And after all, precision engineering has long been needed for the likes of motor car and aircraft engines.
