70 



KNOWLEDGE. 



[March 1, 1894. 



to convert the produce in the first year into sUage, and in 

 the second into bay. The land is thus occupied for two 

 years, and the assumption is tliat in this way highly 

 nitrogenous crops will be obtained with mineral, but with- 

 out the highly-expensive nitrogenous manures, and that 

 the land will be left in high condition for the growth of 

 saleable crops, such as potatoes or grain, which require 

 nitrogenous manuring. In other words, the plan is to 

 grow nitrogen-accumulating crops for home consumption, 

 and afterwards uitrogen-cousuming crops for sale." 



THE FACE OF THE SKY FOR MARCH. 



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



SUNSPOTS show but little, if any, diminution in 

 number. The zodiacal light should be looked for 

 after sunset in the west, during the absence of the 

 Moon. A conveniently observable minimum of 

 Algol occurs at 9h. 24m. p.m. on the 17th. 

 Mercury may be observed as an evening star during the 

 first week of the month. On the 1st he sets at 7h. 21m. 

 P.M., or Ih. 44m. after the Sun, with a northern declination 

 of 1° 26', and an apparent diameter of 8", about VVths of 

 the disc being illuminated. On the 8th he sets at 7h. Om. 

 P.M., or Ih. 10m. after the Sun, with a northern declination 

 of 2° 32', and an apparent diameter of 9|", rather less 

 than Jj^^ °^ ^^^ *^i^^ being illuminated, and his brightness 

 being about one quarter of what it was on February 18th. 

 After this he approaches the Sun too closely to be visible, 

 coming into inferior conjunction on the 14th. While 

 visible he describes a looped path in Pisces, a little to the 

 east of the 6th magnitude star 22 Piscium. 



Venus is a morning star, and is fairly well placed for 

 observation. She rises on the 1st at 5h. 18m. a.m., with 

 a southern declination of 6° 59', and an apparent diameter 

 of 54^", TTo'-l^s 0^ •'1^6 "i'sc being illuminated, and the 

 apparent brightness of the planet being about equal to what 

 it was on February 2nd. On the 12th she rises at 

 4h. 43m. A.M., with a southern declination of 8° 46', and 

 an apparent diameter of 46^'', tVo*-1is of the disc being 

 illuminated, and the apparent brightness of the planet 

 bemg about equal to what it was on January 23rd. On 

 the 22nd she rises at 4h. 20m. a.m., with a southern 

 declination of 9° 23', and an apparent diameter of 49^", |ths 

 of the disc being illuminated, and the apparent brightness 

 of the planet (she being now about her greatest brilliancy) 

 being slightly less (in the proportion of 204 to 218) to 

 what it was on January 11th. On the 81st she rises at 

 4h. 5m. a.m., with a southern declination of 9° 3', and an 

 apparent diameter of 34", .^-^ths of the disc being 

 illuminated, and her brightness being about equal to what 

 it was on January 22nd. During the month she describes 

 a direct path in Aquarius, being about 3° south of the 2i 

 magnitude star p Aquarii on the morning of the 15th, and 

 about 1° south of the 5th magnitude star f Aquarii on the 

 morning of the 19th. She does not approach any other 

 naked-eye stars very closely. 



Mars is invisible for the observer's purposes. 

 Pallas {cf. " Face of the Sky for February"), is still 

 visible, though she decreases in iDrightness to the 7th mag- 

 nitude by the end of the month. On the 1st her R.A. is 

 9h. lO^m., southern declination 9° 44'. On the 15th her 

 R.A. is 9h. 7m., southern declination 3° 32'. On the 31st 

 her E.A. is 9h. 10m., northern declination 2° 46'. She 

 thus pursues an almost perpendicular path through Hydra, 

 starting from the S.W. of Alphard, and crossing to 6 Hydrse. 

 On the last day of the month at transit she will be in the 

 same field of view with the last-named star, 19° of arc 



following it on almost exactly the same parallel of declina- 

 tion. As the Moon will be absent, this will be a capital 

 opportunity, if the night proves fine, for picking up Pallas, 

 as she transits about 8h. 30m. p.m. A notice of the 

 various measures which have been made of the diameter 

 of this minor planet will be found in " Face of the Sky 

 for April," 1890. 



The minor planet Ceres comes into opposition with the 

 Sun on the 7th, at a distance from the earth of about 

 159 million miles, the planet appearing as a star of the 

 7th magnitude. On the 1st her E.A. is lib. 45|^m., 

 northern declination 20° 14'. On the 15th her R.A. is 

 lib. 33gm., northern declination 21° 32'. On the 31st 

 her R.A. is llh. 21m., northern declination 22° 7'. At 

 transit on the 5th she will be only about 12' of arc •>>■ /» the 

 4-^ magnitude star 93 Leonis. During the month she 

 describes a slightly curved retrograde path from a little to 

 the west of this star in the direction of S Leonis. An 

 account of the various estimations of the dimensions of 

 this minor planet will be found in " Face of the Sky for 

 May," 1890. 



'The minor planet Vesta, the largest of all the asteroids, 

 comes into opposition with the Sun on the 6th, at a distance 

 from the earth of about 125 millions of miles. She then 

 appears as a 6| magnitude star, falling to the 7th mag- 

 nitude by the end of the month. On the 1st her R.A. 

 is llh. 3Hm., northern declination 14° 55'. On the 15th 

 her R.A. is llh. ISJm., northern declination 16° 41'. On 

 the 31st her R.A. is llh. S^m., northern declination 

 17° 55'. She thus describes a retrograde path in Leo 

 from a point just three degrees almost due west from ^, 

 towards S, being at transit on the 9th just 15' of arc due 

 north of the 5^ magnitude star 85 Leonis. For measures 

 of the diameter of Vesta, cf. " Face of the Sky for 

 January," 1890. 



Jupiter, though still the most brilliant object in the 

 evening sky, should be looked for as soon after sunset as 

 possible. He sets on the 1st at Oh. 37m. a.m., with a 

 northern declination of 18° 16', and an apparent equatorial 

 diameter of 37-2". On the 15th he sets at llh. 53m. p.m., 

 with a northern declination of 18° 48', and an apparent 

 equatorial diameter of 35j". On the 31st he sets at 

 llh. 4m. P.M., with a northern declination of 19° 29', and 

 an apparent equatorial diameter of 34|". During the 

 month Jupiter pursues a direct path in Taurus, through a 

 region barren of naked-eye stars. At about a quarter past 

 nine p.m. on the 25th a 10^ magnitude star will be about 

 70" north of Jupiter ; on the evening of the 26th an 8^ 

 magnitude star will be situated about 1' " p the planet, 

 and at about lOh. p.m. on the 30th a IO5 magnitude star 

 will be about i' of arc north of Jupiter. The following 

 phenomena of the satellites occur while the planet is more 

 than 8° above and the Sun 8° below the horizon : — On 

 the 1st a transit egress of the third satellite at 8h. 20m. 

 P.M., and a transit ingress of its shadow at llh. 28m. p.m. 

 On the 2nd a transit ingress of the first satellite at 9h. 27m. 

 P.M., and of its .shadow at lOh. 44m. p.m. On the 3rd an 

 occultation disappearance of the first satellite at 6h. 47m. 

 p.m., and its eclipse reappearance at lOh. 14m. 34s. p.m. 

 On the 4th a transit egress of the shadow of the first 

 satellite at 7h. 26m. p.m., and an occultation disappearance 

 of the second satellite at 9h. 3m. p.m. On the 6th a 

 transit egress of the second satellite at 6h. 35m. p.m. ; a 

 transit ingress of its shadow at 6h. 40m. p.m., and its 

 transit egress at 9h. 3m. p.m. On the 8th a transit ingress 

 of the third satellite at lOh. 26m. p.m. On the 10th an 

 occultation disappearance of the first satellite at 8h. 46m. 

 P.M. On the 11th a transit ingress of the shadow of the 

 first satellite at 7h. 8m. p.m. ; a transit egress of the first 



