SCIENCE. 



47 



Now, the astronomical lantern makes the study of the stars perfectly 

 simple and easy. It is constructed like a dark-lantern, closed on three 

 sides, and on the fourth provided with a ground glass, in front of 

 which maps can be inserted. On each of these maps, which are semi- 

 transparent, is represented a constellation, the places of the stars 

 being indicated by perforations, through which the light shines. The 

 largest perforations are for the stars of the first magnitude, and the 

 smaller, in due proportion, for the lesser stars. The student, there- 

 fore, wishing to observe any particular constellation or cluster, has 

 only to light a candle within the lantern, insert the appropriate slide, 

 and go out into the night. Holding up the lantern in one hand, he 

 can compare the constellation as it appears on the lantern with that in 

 the sky, until he becomes perfectly familiar with the latter. 



It is easy to see how much the use of such a lantern facilitates the 

 whole stud)\ In fact, we think that henceforth no one wishing to 

 become acquainted with the heavens can afford to dispense with it. 

 The increased ease of the study should also enlarge the number of 

 students in this interesting department of science. 



The folloiving testimonials as to its value have been 

 recently received : — 



C. A. Young", Prof, of Astronomy, 

 Priticeton Coll. : I find it to be an admir- 

 ably contrived apparatus for its purpose, 

 — simple, easily managed, and effective. 

 I think an adequate knowledge of the 



constellations could be obtained by its 

 use, in connection with the little book that 

 accompanies it, more rapidly and easily 

 than from the most elaborate and expen- 

 sive celestial globe. (Aug, 8, 1885.) 



