49 3 



Changes in the Moon's Surface, 



[October, 



Estimations and Measures of the Extent of Linns. 



Authority. 



Epoch. 





Eng. feet. 



5e::r.is 



QzitCii. 



r.e-.irl-:s. 



Schmidt . 



— 





36-449 



5-17 



Crater. 





B. and M. 



1S31 





33,482 



4-83 



Crater. 





Schmidt . 



1866, Oft. 



iS 



48 ::: 



6-go 



Whitish cloud. 





Birt . . 



iS65. Dec. 



15 



::.g20 



11-61 



Whitish cloud. 



Measured 



ij 



1866, „ 



iS 



49.SS5 



7-07 



::sh cloud. 



Measured 



H • • 



1866, „ 



19 



51.650 



7"32 



Whitish cloud. 



Measured 





1S66, „ 



21 



47-627 



675 



Whitish cloud. 



Measured 



Schmidt . 



1S66, „ 



27 



12.790 



i-Si 



Whitish cloud. 





Birt . . 



1S67, Jan. 



*4 



56.100 



7"95 



::sh cloud. 



Measured 



Buckingham 



1867. Mar. 



14 



42.336 



600 



:sh cloud. 



Measured 



Wolf . . 



1867, June 



12 



3*t75* 



4-50 



:sh cloud. 





Birt . . 



1S67, July 



8 



37^23 



5'33 



Whitish cloud. 



Measured. 



,, 



1S67, „ 



9 



_— 20 



7*00 



Whitish cloud. 



Measured 



,, • • 



1867, .. 



10 



57 '-5 



536 



:;sh cloud. 



Measured. 



Schmidt . 



1866. Dec. 



13 



1,918-4 



0-27 



Delicate hill. 





,, 



[866, .. 



26 



1.695 



0-24 



Fine black point. 





,, . . 



1S67. Jan. 



25 



1,279 



o-iS 



Fine black point. 





»» 



1S67, „ 



25 



1,918-4 



027 



Fine white peak. 





Secchi . . 



1867, Feb. 



11 



2,352 



o-33 



Small crater. 





Respighi 



1867, Apr., 



May 



28,224 



4-00 



Small crater. 





Wolf . . . 



1S67, June 



12 



7056 



I'OO 



Small crater. 





remainder of the spot. This slight extra elevation has 

 already been described by Schmidt. Atmospheric circum- 

 stances did not allow me to obtain an irreproachable image 

 of the moon before the 10th June. On that day, at S o'clock, 

 Linne had already been in full light nearly 4S hours, and 

 the central hole could be seen with perfect sharpness. It is 

 a deep crater — deeper than most of the little craters 

 surrounding it, if one may judge from the comparative 

 intensity of the shadows ; but its diameter is not equal to 

 that of craters A and B of Beer and Madler. The white 

 spot which spreads radiatingly (s'etend en rayonnant) round 

 it, had, on the 12th June, a diameter of 4*5", that of Bessel 

 being j'j" ; the crater itself subtending a little less than 

 one second. The perfect purity of the atmosphere, and 

 the optical power of the telescope which I employed, 

 allowed a number of small craters to be seen very distinctly 

 round Linne, or rather a number of small round holes with- 

 out elevated margins, and which are not shown in Beer and 

 Madler's map. Six of these little craters form a very 

 remarkable double range to the north and north-east of 

 Linne. They are smaller than the craters in a line situate 

 to the north-west of Linne, and noticed by Schmidt. I em- 

 ployed magnifications of 235, 3S0, and 620 times. 



" The brightness of Linne has not changed since Beer 

 and Madler's observations, for it is always equal to that of 

 the white spot situated near Littrow, on the western margin 

 of the Sea of Serenity, to which B. and M. assigned the 

 luminosity 6. 



