Jan. 9, 1885.] 



KNOWLEDGE 



31 



XIGHT SKY FOR JANUARY (First Map of Paik), 



Showing the heavens as they appear at the following hours : — 



January 7 at 10 o'clock. 

 January 10 at Of o'clock. 

 January 14 at 9^ o'clock. 



January 18 at 9{ o'clock. 

 January 22 at 9 o'clock. 

 January 25 at h^ o'clock. 



January 29 at 8J o'clock. 

 February 2 at 8i o'clock. 

 February G at 8 o'clock. 



THE TOUXG ELECTRICIAN. 



By W. Slingo. 



THE study of electricity has of late years increased so 

 extens-ively that there is scarcely a youth who has 

 not, to a greater or less extent, some acquaintance 

 ■with it. There is, too, every prospect that as time goes 

 on, the Eulject will still further increase in po])ularity. 

 As, however, jihysical science i.s based upon experiment, 

 it follows that to gain anything more than tlje merest 

 smattering of the subject, something beyond a few hazy 

 notions culltd from indifferent sources is essential. It 



is necessary, as niucli so, perhap.s, as in' any ether subject, 

 that the study of the science should be practical, and that 

 experiments should be worked to prove the various points 

 laid down. 1 know of no better exercise than having a- 

 certain law in mind to devise apparatus in some form 

 or other to prove its tiuth. But to the ttudent 

 who attempts unaided to unravel for himself lh& 

 mysteries of electrical science, obstacles present themselves 

 at every step. Books there are in shoals to teach him the 

 ).rinciples and applications of electricity ; some, too, describe- 

 in greater or lei-s detail the construction of the spparatUR 

 tmplojed ; but he will look in vain for a work theoietically 

 reliable, and, at the same time, mechanically explicit. Iii 



