1050 SEC. 19. EDUCATIONAL APPLIANCES. 



4289. Spark Inductor, according to Ruhmkorff. 



4290. Induction Apparatus for fundamental experiments. 



4291. Steel Magnet, with five thin plates and keeper. 



4292. Dipping Needle, with stand. 



4293. Magneto-electrical Induction Apparatus. 



4294. Blasting Apparatus for Mining. 



E. Leybold's Successors, Cologne. 



Electricity. 



4295. Electrical Machine, according to Winter, with 

 different connexions for the condenser. 



4296. Holtz's Induction Machine. Diameter of the 

 rotating wheel 520 mm. 



4297. Chime with five bells. 



4298. Ply-wheel on a circular track. 



4299. Lanne's Measure Bottle. 



4300. Discharging Bod. 



4301. Double Ply-wheel. 



4302. Battery of four Leyden Jars. 



4303. Pair of fine Gold-leaf Electrometers. 



4304. Fair of fine Gold-leaf Electrometers, with Zam- 

 boni's Column, improved according to Fechner. 



E LeybolcCs Successors, Cologne. 



SECOND SERIES. APPARATUS AND INSTRUMENTS 



FOR ELEMENTARY SCHOOLS. 



Kinematics, Statics, and Dynamics. 



4305. Inclined Plane, simple. 



4306. Windlass (Gopel). 



4307. Bod Windlass. 



4308. Wooden Screws, with threads of different section. 



4309. Wheel on Axle, with stand. 



4310. Reel, with stand. 



