40 
—WATORE 
[May 13, 1886 
tion with the clamp of the instrument both west and east. It is 
better in his opinion to determine for each instrument the 
necessary corrections to be applied by means of the methods and 
formulz explained in this paper. 
In discussing the flexure of vertical circles Prof. Harkness | 
compares Repsold’s method of eliminating the flexure, by inter- 
changing the object and eye-end of the telescope, with Bessel’s 
method of attaining the same result by observing a star both 
directly and by reflection with the clamp successively west and 
east, demonstrating the superiority of the latter method, which 
appears to be the most satisfactory procedure hitherto devised 
for freeing an observed declination from the effect of flexure. 
Prof. Harkness shows that when there are terms in the flexure 
depending on multiples of the zenith distance, they cannot in 
general be completely eliminated, and therefore that star-places 
derived from observations made with a single instrument are 
likely to be affected by systematic errors, which will appear 
when the work of different instruments is compared together. 
The detection and elimination of such errors can probably, 
Prof. Harkness thinks, be greatly facilitated by the use of equal 
altitude instruments of the zenith telescope class, which are so 
remarkably free from systematic errors. 
THE SPECTRUM OF FABry’s Comet.—M. Trépied having 
frequently observed the spectrum of this comet since April 7, 
gives (Comples rendus, vol. cii., No. 18) the following account 
of it. The three usual cometary bands were seen, and as the 
brightness of the spectrum allowed a fairly narrow slit, 0°2 mm., 
to be used, the coincidence of these bands with those of the 
hydrocarbon spectrum could be very satisfactorily verified. 
Besides these bands there was also a continuous spectrum, but 
the remarkable feature of the case was that although the nucleus, 
which was very distinct and of a truly stellar appearance, ap- 
peared very bright as compared with the neighbouring portions 
of the coma, the band spectrum given by these latter and by 
the tail was much more brilliant than the continuous spectrum 
of the nucleus. This circumstance, which was also observed by 
MM. Thollon and Perrotin at Nice, had been remarked by M. 
Trépied in Encke’s comet last year. He is therefore led to 
conclude that there is a predominance of gaseous elements in 
both these comets, and that, further, the relative brilliance of 
the nucleus of a comet is not necessarily in accord with the 
degree of condensation of the cometary matter. 
On April 14 the bright bands could be easily detected in the 
spectrum of the tail to a distance of 20’ from the nucleus. The 
total length of the tail was then more than 3°. 
Two New Comets.—Mr. W. H. Brooks, Red House Ob- 
servatory, Phelps, New York, discovered two new comets in the 
last week of April, the first on April 27, the second on April 
30. The former is described by M. Bigourdan as being on 
May 1 a round nebulous object, about 2’ in diameter, brighter 
towards the centre, but without a nucleus. The existence of a 
very faint nucleus was, however, suspected on the following 
night. On May 6 Lieut.-Col. Tupman estimated the comet as 
being of the 8th magnitude. Dr. H. Kreutz has computed the 
following elements and ephemeris for it :— 
1886 June 679585 Berlin M.T. 
202 55°68 } 
i 
2% = 191 48°58 > Mean Eq. 18860 
Z(= 87, 33103) 
log g = 9°40752 
LEphemeris for Berlin Midnight 
1886 R.A. Decl. Log 4 Brightness 
eens C ’ 
May 13 2 9 38 51 43°7 N. 01062 2°2 
17 2 30 25 47 52°2 0996 2°9 
2r 2 49 32 43 25°9 0931 471 
25 3 7 48 38 17°2 0865 6°2 
29 3 26 26 32 15°33 N. 0°0794 100 
The brightness on April 29 is taken as unity. 
The second comet is described (Astr. Nach. No. 2728) by the 
Baron von Engelhardt as being very bright on May 3, although 
the evening was misty. The comet was visible in a bright field, 
and showed a circular nucleus, from whence proceeded a brighter 
offshoot, 2’ in length, in the direction of the axis of the tail. 
The tail was 8’ in length and very bright, narrow at first, but 
broadening by degrees, and curved with the convex side towards 
the north. A secondary tail, 6’ in length, faint, and bending 
towards the south, forked off from the principal tail about 6’ 
from the nucleus. The following elements and ephemeris are 
by Dr. E. Lamp :— 
T = 1886 May 4°13040 Berlin M.T. 
wo = 37 5015) 
Q = 287 22°88 - Mean Eq. 1886:0. 
4 = 99 47753 | 
log g = 9°92518 
Error of middle place (O — C). 
dA = +0719 
Ephemeris for Berlin Midnight 
dB = — 0''02 
1886 R.A. Decl. Log + Log 4 Bright- 
h. m. s 3 a ness 
May I2 23 52 46 47 23:00N. 9°9326 9'9924 1°0 
14 0 5 38 51 238 9°9364 9°9980 o'9 
16 0 20 38 55 10°5 9°9410 070056 09 
18 0 38 9 58 39°8 9°9462 o'01l49 O'8 
20 o 58 38 61 49°5 9°9520 0'0255 o'8 
22 12215 64 35°6 9°9583 0°0373 0°7 
24 %I 49 21 66 558 9°9652 O'0501 0'6 
26 219 47 68 48-4 9°9725 0°0636 o'5 
25)  2E52 55s 7Onltey 99802 0°0775 0O'5 
30 «3:27 37 71 +S8N. 9 9881 o0918 0% 
The brightness on April 30 is taken as unity. 
New MINor PLANET.—A new minor planet, No. 258, was 
discovered on May 4 by Dr. Luther at Dusseldorf, R.A. 
15h. 20m., Decl. 9° 31’ S. ; daily motion, R.A. — 48s., Decl. 
7s map. ir. 
ASTRONOMICAL PHENOMENA FOR THE 
WEEK 1886 MAY 16-22 
(Pos the reckoning of time the civil day, commencing at 
Greenwich mean midnight, counting the hours on to 24, 
is here employed.) 
At Greenwich on May 16 
Sun rises, 4h. 8m. ; souths, 11h. 56m. 9°3s. ; sets, 19h. 44m. ; 
decl. on meridian, 19° 9’ N.: Sidereal Time at Sunset, 
1th. 22m, 
Moon (Full on May 18) rises, 17h. 51m. ; souths, 23h. 5m. ; sets, 
4h. 1om.* ; decl. on meridian, 11° 22’ S. 
Planet Rises Souths Sets Decl. on meridian 
h. m. h. m. h. m. Gy 
Mercury 3 34 10 24 17 14 0° 72Ne 
Venus ... 2 48 9 4 15 20 2 29 N. 
Marsi nec lees 19 13 273% 8 57 N. 
Jupiter... TQy 525 ee eeOutO) 2 28* 253 N. 
Saturn .. ONS 7a eee LA eA9 gy ut 22 49 N. 
* Indicates that the setting is that of the following morning. 
Occultations of Stars by the Moon (visible at Greenwich) 
Corresponding 
angles from ver- 
May Star Mag. Disap. Reap texitoriphtiter 
inverted image 
h. m. h. m. a ° 
17 ... 9 Libre m5 (3 *) 22 LOW ee ou S2 64 240 
19 ... 24 Scorpii als © 37 near approach 167 — 
21 ... @ Sagittarii Gey 22 eel eee obi, 19 266 
22) ea BbeadG OOS Sm 0 5 2 near approach 206 — 
Variable Stars 
Star R.A. Decl. 
eee. a 4 h. m. 
¢ Geminorum 6 574... 20 44 N. ... May 20, 2 20 m 
WeVirginiss..) 7013209 2°35 Ss macs aRLETS M 
3 Libre wie 14 54°9 Yeckwmeres pq eh S77 
U Ophiuchi... 17 10°8 I 20N », 16, 0 44 m 
A sea: 
X Sagittarii... 174054) .... 27047 Sa ee eee lO ee ura 
en e22,OmmOMy 
W Sagittarii 17) 57.:8x2-029) 359s. 2. Oe mz Ny Re A ORAZ 
Blyre.. = 18 45:9)... 33, 14 Ne .20 955 oO; eO pon 
S Vulpeculz 19/4357 cos 27OLNe cee eenlics m 
n Aguile ons) LQ)A057) 505 Ole 7EINat eee eSyELO; mOMMOMa/2 
5 Cephei i) -22;824'5O) meaSe7) SOMN a eee amey meee Osman mzze 
M signifies maximum ; 7 minimum. 
