KEPLER's NOVA, 1604.—We learn from Prof. Winnecke that, in consequence of the remarks upon this star which appeared in NATURE, vol. xi. p. 249, he has lately examined the neighbourhood, and, in addition to the star of 11.12th magnitude there mentioned—the position of which for 1855.0 he finds to be R.A. 17h. 22m. 4.6s., N.P.D. 111° 23.6′—he found one of 12th magnitude in R.A. 17h. 21m. 49.3S., N.P.D. 111° 19.3′. This star agrees almost precisely in place with the 10th magnitude marked upon No. 52 of Chacornac's charts, though not at present of that brightness; but we are able to state that in August 1871 and June 1872 nothing was visible in this position in a telescope which would show stars to 13.14 magnitude in Winnecke's scale. It will be desirable to watch this small star closely, as it is quite possible it might be identical with Kepler's famous star, the observed place of which is not so accurately known as in the case of the similar object observed by Tycho Brahe in 1572. Prof. Winnecke, however, suggests that, as the star marked by Chacornac is just upon the margin of his map, where some distortion exists, it might possibly be identical with No. 16,872 of Oeltzen's Argelander, a star estimated 8.9 in the Bonn Zones; still the place of the 12th magnitude agrees much more closely with that of Chacornac's 10th, read Off from his chart as nearly as the circumstances permit. It may be well to compare the fainter star found by Prof. Winnecke, from time to time with the 11.12th close at hand, and easily identified if the instrument be set for Argelander's star, which may be considered a bright 9th magnitude.