On seeing the Red Flames on the Sun's Limb with a Common Telescope

Abstract

ON observing the partial eclipse of the sun on Dec. 22, 1870, it occurred to me whether it might not be possible to see the red flames on the sun's limb without waiting for a total solar eclipse, or whether it was possible to make an artificial eclipse sufficiently perfect to admit of the red flames being seen. Accordingly I cut out several circular discs of thin brass (blackened on both sides), leaving three arms projecting from the periphery of each of such length that when the ends were bent they should slide into the tube of the eye-piece. I placed one such disc in the eye-tube as near to the field lens as possible to avoid its getting hot; but here a difficulty presented itself which I had not foreseen,—the disc was a trifle too large, and it shut out the sun altogether. I put in a smaller one which admitted too much of the sun's light. I afterwards tried several, and it required a considerable amount of filing and scraping to produce one just the right size to cover the sun's disc and no more; especially as the least jarring or vibration of the telescope would cause the edge of the sun to be seen first on one side and then on the other. After several trials at different times I succeeded on January 16, 1872, in seeing on the south-western limb a red flame. It appeared rather wider at the top than the bottom with a smaller one growing out from the bottom or root close to the sun's limb. There was another tongue of flame a little to the right, which appeared to be detached from the larger flame and also from the sun's limb.