To go back to the earlier history of the comet, before these drawings were made, we find that its tail was not observed telescopically until seventy-three days after Donati’s discovery. It was seen on August 14, 1858, by astronomers at Copenhagen and Vienna, but not at Harvard until the 20th of that month. The brilliancy of the comet was somewhat impaired by a strong twilight and its low altitude. This may account for the fact that it was described as ruddy in hue, and concentrated, and having a mere suggestion of a tail. On August 23 the tail was still so faint as to be easily overlooked in the moonlight, the record being: “Bright, but no trace of a tail; the sky clear, but the moon nearly at full.” On August 30, according to the record in the _Times_ (London), of observations made by J. Russell Hind, “The comet was just perceptible to the naked eye; its nucleus is strongly condensed and brilliant, and the tail is thrown off in the ordinary form, without bifurcation.” During the month of September the tail of the comet showed a tendency to curve, and by September 7 it was recorded as being very conspicuous to the naked eye. September 12 it had increased wonderfully in brilliancy, and on September 16 the first sketch was made by G. P. Bond, showing a view of it with the naked eye. The tail was now estimated as being 7° long, thus exceeding the distance (of 5°) separating the pointers. A tangent to the convex edge near the nucleus prolonged would pass through Delta in Ursa Major, and it was noticeable that this side was the brightest in all the sketches. A narrow dark channel extending from the nucleus up the axis of the tail was very remarkable, and its edges were surprisingly well defined, especially very near the nucleus. In fact, the comparatively sharp definition of the eastern edge of the tail was in marked contrast to the softness of outline on the western side. (See _Monthly Notices_, R. A. S., Vol. XIX, pp. 88–89.) By September 27 the length of the tail as observed with the naked eye was about 9° or 10°. It was curved, convex toward the star Cor Caroli, being much better defined on the side near the star than on the concave side. The narrow dark stripe in the axis of the tail was still very marked, and the outline of the tail could be traced from the nucleus halfway to Delta in Ursa Major, and a degree or so further. It was now strongly curved and its upper outline well defined and bright as compared with the inner. A straight ray or secondary tail could be seen faintly suggested on the eastern side and reaching northward from the main tail.