Astronomy and Meteorology. 297 
_ reading off the measure by means of an achromatic microscope, on the 
_ Stage of which it is placed. One of the webs is brought to the intersec- 
_ ttoss-wires, The parts of a revolution are read off by a vernier from a 
__, the advantages arising from the peculiar construction of this microme- 
_ ter are the following : — 
___ 1. Distances can be observed with great accuracy up to about one 
__ degre, and the angles of position also 
4A “aR magnifying power may be used on each of the objects ; 
sd : : : ; ' 
: 8, New Double Stars discovered by Mr. Alvan Clark ; communicated 
4 by the Rey. W.R. Dawes. (From Monthly Notices of the Royal Astro- 
-Tamteal Society, xx., p. 55. Second series.) 
- Care, Date of 
Na Designation, i860, 1560. Mag. _Dist. coed 
mis} : hm s of " 
1 Talande 1980 t o5r 45 324 8 8 0-45 1858, Nov. 29 
© Talande 2634 ~ 1 90 a BO Eg’! OB 1B5E Oct 13 
‘9 
208 38 38574 6, 118 38 1859, July 19 
20 25 41 53320 «= 6}, 11 2B 1859, July 6 
9 AZ xxiv. 11 211050 26102 74, 7 +09 1859, July 8 
75 Cygni 213441 47216 5$,11 29 1859, July 19 
, Steg double stars in this series may be considered as good tes 
T telescopes of from 6 to 8 or 9 inches aperture. But it is not 
- Either, therefore, they have recently undergone considerable 
1 OF, if not, it appears that objects of great difficulty and delicacy 
detected with very perfect telescopes of smaller size, which have 
daette Most diligent scrutiny with far larger instruments. The whole 
| discov: b 
a "evious one by hie father with the Dorpat telescope of 9°6 inches 
May : 
a S005 1Y rejected, It appears, therefore, that there is still much oc- 
5 SERIES, Vor. XXIX, No. 86.—MARCH, 1860. 
38 
