MAGNETISM. 



1 



FIG. 2643. FIG. 2644. 



FIG. 2674. 



FIG. 2646. 



FIG. 2674*. 



MAGNETIC AND ELECTRO-MAGNETIC APPARATUS. 



2642 Loadstones, or Natural Magnets, specimens each 5s ; 



7s. 6d. 



Magnets, Permanent, of Steel, Horse-shoe shape, from 

 1 to lO.inches in length (fig. 2643) each 6d., Is., Is. 6d. 



Magnets, Compound Horse-shoe form, of various sizes, 

 with 2, 4, 6, or 8 Magnets, combined with soft Iron 

 keepers (fig. 2644) .... 10s., 16s., 21s. 



Magnet Bar, 6 inches long, round or flat . each 



Magnets, Bar, in pairs, of flat shape 6-inch and 12-inches 

 long ; in wood bos, with soft Iron keepers (fig. 2646) 



Magnet Bar, of large size, used for adjusting and 

 correcting Ships' Compasses 



Magnetic Needles, mounted with Brass centres . 



Ditto ditto Agate centres (fig. 2649) . 



Stands or Supports for ditto 



Astatic Needles, to suspend on a point, or by a silk 

 fibre or hair ........ 



Dipping Needles, with graduated Arc simple form 



Ditto ditto with graduated Circle 



Dipping Needle, extremely delicate, with divided 

 vertical and azimuth circles, spirit level, and adjust- 

 ing screws (fig. 2660) 



Oersted's Apparatus or Experiment, for showing the 

 deflection of the magnetic needle by an electrical 

 current passing above or below it, simple form 



Ditto ditto (fig. 2662) 



Oersted's Experiment, of extra large size, the Needle 

 mounted either vertical or horizontal, suited for 

 Lecture Table 



This apparatus will illustrate the principle of the electric telegraph in its 

 most elementary and simple form 



s. 

 10 



s. d. 



i 6 



2643 



2644 



2645 

 2646 



2647 



2648 

 2649 

 2650 

 2651 



2658 

 2659 

 2660 



2661 



2662 

 2663 



026 050 



220 



3 



2 6 



10 6 110 



3 

 10 

 1 



12 



1 5 

 5 5 





 

 

 



1 

 1 



10 



16 



6 



15 



2 6 



1 



10 



10 



15 15 



7 

 16 



10 6 

 15 



2 10 



