DISCOVERY OF NEW RILLS ON THE MOON FROM THE LICK OBSERVATORY NEGATIVES. By Professor L. WEINEK, Director of the Observatory of Prague. [Abstract by Professor HOLDEN.] Professor WEINEK has asked me to communicate to the Society a brief account of new rills which he has discovered in his examination of the negatives of the moon made at Mt. Hamilton. It was hoped to accompany this note with reproductions of Professor WEINEK's exquisite drawings, but it is not possible to do so, at present. The drawings will appear in due time in the Publications of the Observatory of Prague, and also in a volume to be printed by the Lick Observatory by the aid of the generous gift of Mr. LAW. (See Publications A. S. P., vol. iii, P. 377.) Cleomedes (drawn 20-fold enlarged, Nov. 19, 1891, from the Mt. Hamilton negative of August 31, 1890, 14h 27 P. s. t.). Between craters B and i (NEISON). The westernmost rill originates at the foot of a hill north of c, and can be traced up to an angle in the west wall. There is a short rill crossing the first described. Both these rills show bright edges (walls) and seem, therefore, to be real. Other rills are shown on Professor WEINER'S drawings. These rills should be verified either on other plates (not now available) or at the telescope. Eimmart (drawn 20-fold enlarged, Nov. 22, 1891; discovered Nov. 21, on the Mt. Hamilton negative of Aug. 23, 1888). Two long rills extending east and west, south of Eimmart S (SCHMIDT). These have bright walls and are well seen on the plate taken 1890 Aug. 31, 14" 25" and not so well on the plate taken at 14" 27 on the same night. They are crossed by many others which are not so certain. Picard (drawn 20-fold enlarged, from the Mt. Hamilton negative of Aug. 31, 1890, 14h 25m P. s. t.). New rills discovered Dec. 1, 1891. 1. North of Picard; fork-shaped, and with bright walls. 2. West of Picard; rill with crater formation; probable. 3. Also rills east of Picard. A drawing is required to explain the situation of these objects. Longomontanus (drawn 20-fold enlarged, from the Mt. Ham ilton negatives of Oct. 12, 1891, 7h 29m 75–115 P. s. t. and of Oct. 12, 1891, 7 30 53-56 P. s. t.). New rills discovered 1892 Jan. 31. 1. Extending right through Longomontanus from south to north with a knee in the middle towards the west. Bright walls. 2. In the southern interior portion, crossing No. 1, and extending to the central peak. 3. Rill east of and close to the central peak. 4. Valley to the central peak towards the north, etc. The foregoing bare catalogue seems to do scant justice to Professor WEINE K's discoveries as they are exhibited on the beautiful pencil drawings now at the Lick Observatory, but it is unfortunately all that can be given at this time, as these drawings require the most perfect processes of copying (heliogravure) in order to represent the originals. E. S. H. |