2-982-466 - The Print Collector/Heritage Images

Telescopic Appearances of Donati's Comet, as seen from Slater's Observatory, on the Morning of Oct. 1, 1858. Drawing of '...the Comet as it appeared on the morning of October 1st, at five o'clock, through the 15-inch 20-feet refractor of Mr. Slater, at the Observatory, 136, Euston-road, London. The nucleus was very bright, also the beautiful circle of light that then surrounded it. This brush-like circle somewhat resembled the tail of a peacock when spread open. From the lowest part of the nucleus towards the tail there was an opening about 15" wide, and the contrast of the dark sky through this opening with the light of the tail was very striking, particularly so close to the nucleus. The horned appearance of this brush of light at the opening, and the "tunnel-like" shape it assumed showed distinctly a very considerable thickness-certainly not less than its diameter. The light of the brush appeared steady, but that of the tail at the upper part very much resembled the motion of fine particles of dust as seen in a darkened room when the sun is shining upon them...Mr. Slater's telescope is the largest refractor at present in use in this kingdom, the effective aperture of the object-glass being 14.8 inches, and the focal length 20 feet 4 inches'. From "Illustrated London News", 1858.