256 REPORT— 186G. 



lines intersecting at that point, the one from Tycho is the most recent. Now 

 the ray from Tycho, on which the fault IV A" ^^ occurs, is nearly parallel with 

 the one on which IV A^^^ is found, and it may be of nearly the same age. 

 The fault IV A" l ' , IV A/3 20^ IV A« 72^ ^i^ich intersects IV A" 23^ jg nowhere 

 ohlitemtcd between IV A" 2 and the north border of Ehteticus, while in the 

 neighbourhood of IVA/^l^ the fault IV A" 23 ^g obliterated, the elevated 

 ground on which the crater is situated effacing it. Does this point to a more 

 recent epoch than that of Tycho for the outburst of the crater IV A'' 2 ? Also, 

 Is the fault IV A" 23 more recent than the ray from Tycho on which it 

 occurs ? 



73. A rill from IV A'* 28 to IV A« ^<^, length 21"-87. Schmidt, N"o. 363. 

 Schmidt discovered this rill in 1853, on May 14, with the Berlin refractor. 



He describes it as having a N.E. and S.W. direction, and extending from 

 Hipparchus y to Eeaumur /3 of 13. & M.'s map. It is very faintly traceable 

 on the photograph, and may probably be a crater-rill. 



74. A liU crossing Rha3ticus from S.E. to N.W. Schmidt, No. 366. 

 This riU was also discovered by Schmidt in 1853, on May 14, with the 



Berlin refractor. There is another rUl more to the N. in Quadrant I. cross- 

 ing Rh^ticus, probably Nos. 47 and 43 of Schmidt's Catalogue. These were 

 discovered by him on the same daj-, and with the same instrument with 

 which he discovered the above-mentioned rills, viz. Nos. 363, 364, 365, and 

 366. Both the rills in Ehoeticus are apparent on the photograph. 

 J75. The continuation of the shallow part of the vaUey IV A^ ^^. 

 X7G. The depressed portion of the valley IV vV* '^■^ discovered by "VV. R. 

 Birt, 1866, Nov. 14, with the Eoyal Society's achromatic of 4^-inch 

 aperture, power 230. 

 This object, as well as the valley of which it forms part, is very evanescent, 

 being visible only about the time of sunjrise. 



77. A valley-like depression running S.W.-N.E. between the faults 

 IV A^ 20 and IV A«« ^9, from IV A^ 30 to IV A« 78, 



78. A crater in the angle between IVA«*38 and IV A* "^8, length 

 E.-W. 9"-03, breadth S.-N. 4"-76, mag. 0-42. 



79. A depression on the S.W. slope of IV A* ^*, most probably b of 

 B. & M., length 4"-76. 



80. A mountain -range running between IV A* 23 ^nd IV A* ^^, length 

 of crest 22"-82. Probably the S.E. side of Lohrmaun's 87, Sec. I. 



81. A depression on the S.w! slope of IV A* 54^ N.N.W. of IV A« '9, 

 length 6"-66. 



82. A small depression north of IV A* ^3. 2"-3, mag. 0-15. 



83. The ray from IV A<* 4 to IV A« 3<^. 



84. A mountain-peak on the N.W. border of Eeaumur in conti- 

 nuation of IV A'*^ 9, length 6"-18. IVA«'^ IVA«19, and 

 JYA.««84 foi-m an almost continuous mountain -chain on the N.W. 

 border of Eeaimiur, length 22"-35. This mountain-chain is con- 

 nected with IV A^ 28 ty the rill IV A* ^3, 



85. A shaUow depression west of IV A'* 7o. 3' .33, 



