By Stephen F Tonkin
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Dio Cassius (Cassius Dio), ca. a hundred and fifty– 235 CE, was once born at Nicaea in Bithynia in Asia Minor. at the demise of his father (Roman governor of Cilicia) he went in one hundred eighty to Rome, entered the Senate, and less than the emperor Commodus was once an recommend. He held excessive workplaces, turning into a detailed good friend of a number of emperors.
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Shoestring Telescopes unit power finder. 125 in (3 mm) plywood. The Diagonal Holder A 6 in scrap section of the spar tube is the diagonal's stalk holder. A 1 in diameter section of broomstick, approximately 8 in (20 cm) long, serves as a stalk to which the diagonal is attached. One end of the stalk was cut to a 45° surface. 25 in (6 mm) plywood, cut to the diagonal's outline, attaches with a screw and epoxy to the diagonally cut stalk. I drilled holes 120° apart inside the edges of the plywood, which has a polyurethane varnish coating.
I drilled each end of the pan reducer with three radial holes which through which I could bolt it to the tin and to the soil pipe. The holes are spaced at not quite 120° intervals. This unequal spacing is useful for ensuring that the arrangement can only be assembled in one orientation. I bolted the tin to the pan reducer, but not the pan reducer to the soil pipe. A glance down the draw-tube revealed that there were no nasty internal reflections, mostly, I think, owing to the light-baffling nature of the internal flanges on the plumbing parts.
The eye-bolts barely clear the mirror's surface. 125 in (3 mm) thick. I salvaged the Styrofoam from a trash heap. 5 in (38 mm) wide which sits flush with the straight edge of each bearing. A coping saw blade trimmed the excess Styrofoam after the door skin was glued to the Styrofoam with common carpenter's glue. Inexpensive fibreglass-reinforced plastic (FRP), pebbly side outward, surfaces the curved portion of the bearings. To prepare the FRP's surface for the carpenter's glue, contact cement was first applied to the FRP.
Amateur telescope making by Stephen F Tonkin