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walls almost can be resolved through binoculars. Just beyond the outer wall on the plain to the northwest look for a cluster of three smaller craters like a rabbit's tracks in the snow. Beginning with the largest and moving clockwise, they are lancre-nus f, lancrenus b, and lancrenus k (Fig. 47). Their respective diameters are 30, 21, and 19 miles, and their depths are 8400, 8500, and 8200 feet.

Just south of strong young Langrenus, equally large but very old and dilapidated Vendelinus has returned to prominence for one night. Where its northeast wall should be we note the large, dark-floored intruder Lame which also is quite old and battered. West of the latter and astride the north wall of Vendelinus is the young crater lohse, 26 miles across and 9700 feet deep, which has a relatively large off-center peak (Fig. 47). Tangent to the south wall is holden, 28 by 33 miles across and 13,500 feet deep, which has no central peak. Holden is about % black while Lohse is only % black.

Continuing south along the terminator about the same distance as the last jump we come to conspicuous Petavius which rivals Langrenus in splendor on tonight's final appearance. The rough terraced walls and large central mountain readily are seen, and a small telescope would show a broad bright rill running from the mountain southwest to the wall and resembling a highway across the floor. Tangent to the northwest wall is Class 1 wrottes-ley, 37 by 43 miles across and 11,300 feet deep. Just beyond the east wall of Petavius look for a bright straight line about 90 miles long which runs approximately north-south. Darkness separates it from the crater wall. That is the east wall of the curious funnel-shaped valley pautzsgh, 11,200 feet deep, concerning which Wilkins and Moore write: "It is generally described as an irregular, gorge-like formation 60 miles long and 20 wide, and it has often been suggested that it was formed by a meteor ploughing its way through the still-plastic lunar surface. On 4 October 1952 Moore, using the great 25-inch Newall refractor at the Cambridge University Observatory, had a superb view of Pa-litzsch, and its true nature was at once evident. It is not a gorge at all, but a vast crater chain." Running south from Petavius is a more conspicuous bright line than the wall of Palitzsch, about the same length and wavy. At first it appears to be part of the same sunlit crest, but it is offset slightly to the west. That is the east wall of the double crater Hase, most of the floor of which is now dark.

Again we go south about the same unit distance to the last of the four vast craters that lie approjj mately equally spaced along the same lunar m®! ridian. Furnerius shows well, more prominent than Vendelinus but inferior to Petavius and Langrenus. Close to Furnerius on the southwest is Class fraunhofer, 33 miles in diameter and 7goo fg^J deep. North of Furnerius and southwest of Petj vius we see the smaller closer pair Snellius and Stevinus. Farther south along the terminator we encounter an increasing profusion of craters, a few of which are large. Abundance and similarity, extreme foreshortening, and the Iibration in latitude complicate identification. We can enjoy the view perhaps even more if we do not feel called upon to name everything we see, a point that should be kept in mind as we explore from night to night.

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