214 



KNOWLEDGE. 



[September 1, 1894. 



down to a clouded white, while there are streaks of the 

 same colour on the flanks. The under feathers of the 

 tail are white, contrasting with the almost black upper 

 feathers. The iris and bill are red, and the bill is rendered- 

 still more striking by a bright yellow tip. Ttie legs, which 

 are of a pale green, have a bright red band just above the 

 so-called knee. It may here be said that what is generally 

 known as the knee of a bird is in reality the tarsal or 

 ankle joint, and not the knee at aU ; the knee joint being 

 higher up and concealed by skin and feathers. 



The young birds of the year are lighter in colour than 

 the mature birds, and they have green beaks. 



THE FACE OF THE SKY FOR SEPTEMBER. 



By Herbert Sadler, F.R.A.S. 



THEBE is but little diminution at present in the 

 number of spots on the solar surface. There will 

 be a total eclipse of the Sun on the 29th, which, 

 however, will be invisible in Europe or America. 

 Conveniently observable minima of Algol occur at 

 lOh. 16m. P.M. on the 5th ; at 7h. 5m. p.m. on the 8th; at 

 llh. 58m. p.m. on the 25th ; and at 8h. 47m. p.m. on the 

 28th. 



Mercury is too near the Sun to be observed this month ; 

 he is in superior conjunction on the 3rd. 



Venus is a morning star, rising on the 1st at 3h. Im. 

 A.M., or 2h. 12m. before the Sun, with a northern 

 declination of 16° 25', and an apparent diameter of 10|", 

 ^^ths of the disc being illuminated, and the apparent 

 brightness of the planet being about what it was on 

 February 8th. On the 10th she rises at 3h. 27m. a.m., or 

 2h. before the Sun, with a northern declination of 13° 5', 

 and an apparent diameter of 10|", yV^jths of the disc being 

 illuminated. On the 20th she rises at 3h. 57m. a.m., or 

 Ih. 47m. before the Sun, with a northern declination of 

 8° 48', and an apparent diameter of 10-4", -rVo^'^s of the 

 disc being illuminated. On the 30th she rises at 4h. 29m. 

 a.m., or Ih. 30m. before the Sun, with a northern declination 

 of 4° 6', and an apparent diameter of 10^", yggths of the 

 disc being illuminated. During the mouth she pursues a 

 direct path through the whole of Leo into Virgo, being 

 just over ^° north of Regulus on the morning of the 11th. 



Mars is an evening star, and is becoming very well 

 situated for observation. He rises on the 1st at 8h. 34m. 

 P.M., or Ih. 48m. after sunset, with a northern declination 

 of 9° 15', and an apparent diameter of 17-4", the phase on 

 the s p limb amounting to 1-7". On the 8th he rises at 

 8h. 8m. P.M., or Ih. 39m. after the Sun, with a northern 

 declination of 9° 37', and an apparent diameter of 18-4", 

 the phase amounting to 1-5". On the 18th he rises at 

 7h. 29m. P.M., or lb. 22m. after the Sun, with a northern 

 declination of 9° 50', and an apparent diameter of 19-8'', 

 the ijhase amounting to l-l" On the 30th he rises at 

 6h. 36m. P.M., or 55m. after the Sun, with a northern 

 declination of 9° 37', and an apparent diameter of 21-1", 

 the phase now only amounting to 0-6". During the mouth 

 he describes a short curved path to the N.E. of the 4^ 

 magnitude star Ji Ceti, on the confines of Cetus and Aries", 

 the planet being situated between f' Ceti and i Arietis (5s 

 magnitude), and being stationary in the heavens on the 

 15th. On the evening of the 2nd an 8i- magnitude star 

 will be closely n p the planet. 



Jupiter is an evening star in the sense of rising before 

 midnight. On the 1st he rises at llh. 11m. p.m., with a 

 northern declination of 23° 4', and an apparent equatorial 

 diameter of 36-0", the phase on the /< limb amounting to 

 0-3". On the 7th he rises at lOh. 51m. p.m., with a 



northern declination of 28° 3', and an apparent equatorial 

 diameter of 36V'. On the 18th he rises at lOh. 14m. p.m., 

 with a northern declination of 23° 1', and an apparent 

 equatorial diameter of 37f". On the 30th he rises at 

 9h. 26m. p.m., with a northern declination of 22° 59', and 

 an apparent equatorial diameter of 39:1^', the phase 

 amounting to 0'4". The following phenomena of the 

 satellites occur while the Sun is 8° below and Jupiter 8° 

 above the horizon : — On the 1st an occultation reappearance 

 of the third satellite at Oh. 53m. a.m. On the 2ud an 

 eclipse disappearance of the first satellite at 3h. 13m. 27s. 

 a.m. On the 3rd a transit ingress of the shadow of the first 

 satellite at Oh. 28m. a.m., a transit ingress of the satellite 

 itself at Ih. 43m. a.m., a transit egress of its shadow at 

 2h. 43m. a.m., and a transit egress of the satellite at 

 3h. 59m. A.M. On the 4th a transit ingress of the shadow 

 of the second satelhte at Oh. 43m. a.m., an iiccultation 

 reappearance of the first satellite at Ih. 10m. a.m., a 

 transit egress of the shadow of the second satellite at 

 3h. 14m. A.M., and a transit ingress of the satellite itself 

 at the same time. On the 6th an occultation reappearance 

 of the second satellite at Oh. 42m. a.m. On the night of 

 the 6th Jupiter will appear with apparently seven satellites 

 in a small telescope. At midnight an 8-6 magnitude star 

 will be nearly midway between the first and third satellites, 

 rather nearer the third, the star p the planet about d^' , 

 O'l'. south of the centre. Closely /' the planet at the 

 same hour (between the second satellite and Jupiter), 

 about \^' f and ^' south, will appear an 8-1 magnitude 

 star, which will be just south of the planet's centre at a 

 distance of rather over \' fr'om the southern limb at 4h. 

 A.M. on the 7th. And at the same hour (midnight) on the 

 6th an 8-5 magnitude star will be aboat ^' f the fourth 

 satellite, ;;nd about 2f ' south of it ; at 4h. a.m. on the 7th 

 this star will be 2-^' / Jupiter, and 2^' south. Besides 

 these, there will be sis more stars between 8-i and lOJ 

 magnitudes within a radius of 15' from the planet, making, 

 with the four satellites, thirteen objects visible in a field of 

 30' diameter, with a planet in the centre, on a 2ior 3 inch 

 achromatic. On the 8th an occultation disappearance of 

 the thiid satellite at 2h. 22m. a.m. On the 10th a transit 

 ingress of the shadow of the first satellite at 2h. 22m. a.m., 

 of the satellite itself at 3h. 39m. a.m. ; a transit egress of 

 the shadow at 4h. 37m. a.m. On the lltli an occultation 

 reappearance of the first satellite at 3h. 6m. a.m., and a 

 transit ingress of the shadow of the second satellite at 

 8h. 17m. a.m. On the 12th a transit egress of the first 

 satellite at Oh. 24m. a.m. On the 13th an eclipse re- 

 appearance of the second satellite at Oh. 40m. 39s. a.m., an 

 occultation disappearance of the second satellite at Oh. 49m. 

 A.M., and its occultation reappearance at 3h. 23m. a.m. 

 On the 15th an eclipse disappearance of the third satellite 

 at Ih. 20m. 17s. a.m., and an eclipse reappearance of the 

 satellite at 3h. 43m. 30s. a.m. On the 17th a transit 

 ingress of the shadow of the first satellite at 4h. 16m. a.m. 

 On the 18th an eclipse disappearance of the first satellite 

 at Ih. 28m. 31s. a.m., and a transit egress of the third 

 satellite at llh. 25m. p.m. On the 19th a transit ingress 

 of the first satellite at Oh. 4m. a.m., a transit egress of its 

 shadow at Ih. Om. a.m., a transit egress of the satelhte 

 at 2h. 17m. a.m., and its occultation reappearance at lib. 

 29m. a.m. On the 20th an eclipse disappearance of the 

 second satellite at Oh. 49m. 54s. a.m., of its reappearance 

 at 3h. 17m. 17s. a.m., and its occultation disappearance at 

 3h. 28m. A.M. On the 22nd a transit egress of the second 

 satellite at Oh. 23m. a.m. On the 25th an eclipse dis- 

 appearance of the first satellite at 3h. 21m. 52s. a.m. On 

 the 26th a transit ingress of the shadow of the first 

 satellite at Oh. 38m. a..m., a transit ingress of the third 



