HARD WICKE ' S S CIE NCE- G O SSI P. 



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ASTRONOMY AND METEOROLOGY. 

 By John Browning, F.R.A.S. 



AN interesting discussion has taken place between 

 Professor Hough and Mr. Denning respecting 

 the red spot which has been seen for the last nine 

 years on Jupiter. Mr. Denning says that he has 

 made about 300 observations of this peculiar marking 

 since it became prominently visible and it has 

 exhibited a variable rate of motion. In 1879 it 

 completed a rotation of the planet in 9 hrs. 55 min. 

 34 sec, now it occupies 9 hrs. 55 min. 41 sec, 

 whence it follows that if this spot really forms part 

 of the actual surface of Jupiter, this enormous 

 planet must have increased the length of its day by 

 seven seconds in eight years, which is utterly in- 

 consiste it with probability. The red spot is, doubt- 

 less, an unusually persistent feature in Jupiter's 

 gaseous envelope, but its irregular velocity proves it 

 to be separate from the sphere. Its origin is to be 

 attributed to atmospheric phenomena capable of 

 imparting a very pronounced and durable effect. 



Professor Hough says the rotation period of Jupiter 

 from the red spot has not materially changed during 

 the past three years. The mean period 1884-5 was 

 9 hrs. 55 min. 40 sec. 4. Marth's ephemeris for 

 this year is based on a period of 9 hrs. 55 min. 

 40 sec. 6. 



Continued observations of the red spot will now 

 possess great interest as tending to throw some 

 light on the physical constitution of the giant planet. 



Professor Kirchoff is dead at the age of 63. The 

 discoveries of this great physicist in spectrum 

 analysis rendered it possible to study the chemistry 

 of the heavenly bodies by the aid of the spectro- 

 scope. 



December 12th, Venus will be at the least distance 

 from the sun at 11 hours morn. 



December 26th, Mars will be at the greatest 

 distance from the sun at 8 hours morn. 



There will be no oocultations in December of stars 

 less than a 4th magnitude. 



In December, Mercury will be a morning star 

 throughout the month. 



Venus will be a morning star, entering Libra about 

 the 14th. 



Mars will be in Virgo throughout the month. 



Saturn will be almost stationary in Cancer. 



Meteorology. — At the Royal Observatory, Greenwich, 

 the lowest reading of the barometer for the week 

 ending 15th October, was 29-24 m. on Monday 

 morning, and the highest 30-05 in. at the end of the 

 week. The mean temperature of the air was 41-1 

 deg., and was 10-7 deg. below the average. The 

 direction of the wind was variable. Rain fell on six 

 days of the week, to the aggregate amount of 0-36 in. 

 The duration of registered bright sunshine in the 



Rising, Southing, and Setting of the Principal Planets 

 at intervals of Seven Days in December. 



week was io'i hours, against 23-4 hours at Glynde- 

 place, Lewes. 



For the week ending 22nd October, the lowest 

 reading of the barometer was 30*05 in. at the 

 beginning of the week, and the highest 30*43 in. on 

 Tuesday morning. The mean temperature of the air 

 was 40-3 deg., and 7-4 deg. below the average. The 

 direction of the wind was variable. No rain was 

 measured on any day of the week. The duration of 

 registered bright sunshine in the week was 13*4 hours, 

 against 33 *3 hours at Glynde Place, Lewes. 



For the week ending 29th October, the highest 

 reading of the barometer was 30*39 in. on Tuesday 

 evening, and the lowest 29*15 in. at the end of the 

 week. The mean temperature of the air was 43 * 1 

 deg., and t,"j deg. below the average. The general 

 direction of the wind was S.S.W. Rain fell on four 

 days of the week, to the aggregate amount of 0*29 in. 

 The duration of registered bright sunshine in the 

 week was 25-7 hours, against 24*5 hours at Glynde 

 Place, Lewes. 



For the week ending 5th November, the highest 

 reading of the barometer was 29 * 53 in. on Monday 

 evening, and the lowest 28*63 m - on Friday morning. 

 The mean temperature of the air was 45*4 deg., and 

 1 -3 deg. below the average. The general direction of 

 the wind was S.S.E. and S.W. Rain fell on six 

 days of the week, to the aggregate amount of I '82 in. 

 Tne duration of registered bright sunshine in the 



