360 



EECEEATIVE SCIENCE. 



dislodged, and reposing in my chloroform bottle. 

 Every day I find its use, so think your readers could 

 not do better than get one. I may say that in manu- 

 facture and optical exactness they are most satis- 

 factory instruments. — C. Hope Eobertsox. 



OCCULTATIONS- OV JupITEE's SATELLITES. — ^" An 



Inquirer" wishes to know how it is that a satellite of 

 Jupiter is made to reappear on several different dates 

 without an intermediate disappearance, or vice versa. 

 After a satellite has disappeared behind the planet, it 

 must of course emerge again before it can disappear 

 a second time ; but, unless the reappijarance takes 

 place whilst Jupiter is visible, it is omitted in the 

 list of occultations as unnecessary information. 



Celestial Objects. — It is worthy of note, that 

 during March Venus has been seen in the day with 

 the naked eye as early as half- past four o'clock, and 

 that on the 23rd, at 6h. 45m. p.m., the young Moon was 

 visible at Wari-en Point, Ireland, although new Moon 

 had only occurred at Ih. 56m. p.m. on the 22nd. 



Biological Terms. — A learned Tinker asks to 

 " make a note on what may be called a plauisible mis- 

 use of the word ' elinrinate,' on page 175, It is tnie it 

 means, ' to throw out,' and, tlierefore, may be said to 

 be correctly used to describe colours thus appearing 

 by rotation, but the real sense of the word is, to cast 

 out something superfluous or noxious, or not apropos to 

 what we seek to produce or educe, one of which latter 

 two words should be used in the passage referred to." 



Electric Illumination. — Mr. Faraday, in his lec- 

 ture on " Light-house Illumination," at the Eoyal 

 Institution, spoke in the highest terms of praise of 

 the efficiency of the apparatus in use at the South 

 Foreland High Light. This was placed in the light- 

 house by Professor Holmes, to do duty for the sis 



winter months. There are two magneto-electric 

 machines at the South Foreland, each being put in 

 motion by a two-horse power steam-engine ; and, 

 excepting wear and tear, the whole consumption of 

 material to produce the light is the coke and water 

 required to raise steam for the engines and carbon 

 points for the lamp in the lantern. The lamp is a 

 delicate arrangement of machinery, holding the two 

 carbons between which the electric light exists, and 

 regulating their adjustment; so that whilst they 

 gradually consume away, the place of the light shall 

 not be altered. The electric wires end in the two 

 bars of a small railway, and upon these the lamp 

 stands. When the carbons of a lamp are nearly gone, 

 that lamp is lifted off, and another instantly pushed 

 into its place. The machines and lamp have done 

 their duty during the past six months in a real and 

 practical manner. The light has never gone out 

 through any deficiency or cause in the engine and 

 machine-house, and when it has become extinguished 

 in the lantern, a single touch of the keeper's hand 

 has set it shining as bright as ever. The light shone 

 up and down the Channel, and across into France, 

 with a power far surpassing that of any other fixed 

 light within sight or anywhere existent. The next 

 step will be to adopt this light for the illumination of 

 towns, and in London one such experiment begins to 

 promise a complete success. 



A New Planet, the first of the year 1860, but 

 the 58th of the series of planetoids, was detected by 

 M. Luther, at Bilk, near Diisseldorf, on the evening 

 of Saturday, March 24. The following positions were 

 obtained by the discoverer the same night : — 



B.M.T. E.A. Decl. N. 



March 24.. llh. Om. .. 12h. Im. 56s. .. 2° 51' 



" 24..12h. 14m. .. 12h. Im. 53s. .. 2° 51-5' 



