SCIENTIFIC SUMMARY. 
203 
Royal Astronomical Society. Some small white projections from the S. 
limb, occasionally seen, were not sufficiently steady for delineation. 
The Minor Planets. — Since our last notice, No. 157 has been discovered 
by Borelly, at Marseilles, Dec. 1, 1875 ; No. 158 by Knorre, at Berlin, Jan. 
4, 1876 ; No. 159 by Paul Henry, at Paris, Jan. 26 ; No. 160, in America, 
Feb. 25. Hilda, No. 153, i3 found to have a very long period of 7-85 years, 
and to approach Jupiter as nearly as 0-564 of the earth’s mean distance from 
the sun. 
Jupiter. — Eleven drawings, taken with the same telescope and observer as 
those of Mars, during June and July 1875, have been presented to the 
Royal Astronomical Society. That body has appointed a committee, con- 
sisting of Pluggins, Knobel, Lord Lindsay, Lohse, Ranyard, Lord Rosse, 
Terby, and Webb, to obtain as extensive a series as possible of observations 
and drawings of this planet. A mean of the measures of Struve at Dorpat 
and Engelmann at Leipzig gives for the respective diameters of the satellites 
in seconds and English miles (for solar parallax 8"‘875) I. F'048 ; 2,435. — 
II. 0"*911; 2,115.-111. 1"'513 ; 3,515.— IV. l"-278 ; 2,970. 
Neptune. — Professor Newcomb finds, with the Washington achromatic, 
the orbit of the satellite sensibly circular ; inclination 121*°7. No trace of 
another satellite. Mass of primary, 
Comets. — No new comet appeared in 1875 ; but the return of Encke’s was 
closely observed. Von Asten finds in it an undoubted acceleration, not due 
to a resisting medium, but, as Bessel thought, to the phenomena of a out- 
streaming ” from the nucleus. Ranyard has pointed out the evidence of a 
duplex structure in the comet of Coggia, 1874. With observed, July 8, a 
remarkable oscillatory motion in the fan-shaped jet. Schmidt assigns to its 
nucleus a mean diameter of 290 miles. 
Double and Variable Stars. — The companion of Sirius has been repeatedly 
measured at Washington since 1873. — 40 Eridani. This is an interesting 
.and suggestive group. It is noteworthy in the first place for the large 
proper motion of the lucida, amounting, according to Madler, to — 2 // T88 in 
R.A., and — 8"A10 in Deck Then for its physical connection, as proved by 
community of spatial displacement, with a 9-5 mag. companion, which 
nevertheless has kept its relative position since 1783 : then for the binary 
character of the companion, a pair in undoubted motion : and finally for its 
possible connection with two other small stars in the vicinity. These were 
measured by Winnecke in 1864 at 75 "*85 and 89 //, 45j and fresh measures 
during this winter may prove decisive, as those distances, on the suppo- 
sition of mere optical juxtaposition, would be respectively varied to 4LH 
and 107 // -3. — 44 Pootis. Dr. Doberck at Markree has found the period of 
this star 261T2 years, with a semi-axis major of The same computer 
gives respective periods of 1578 -33 and 349-1 years to £ Aquarii, and 36 
Andromedce. For 7 Cassiopeice he gives 222-435 years, with a semi-axis 
more than twice as great as that of the orbit of Neptune. For the very 
difficult pair <0 Leonis he finds a period of 107*62 years. — y Coronce Australis 
has, accordirig to Schiaparelli, a period of 55-582 years. Burnham has 
found that his pair Leporis is in very rapid motion, 12° per annum . 
— p Cassiopeice. It appears from Smyth’s 11 Cycle ” that there was in his 
time a 6 mag. star just 18' S. of p, of a decided though not deep red. This 
