26 BENJ. PIKE'S, JR., PRICE CATALOGUE. 



No. 



581 Fig. 415, dipping needle, - - $3 to $6.00 



582 Fig. 416, dipping needle, with graduated arch, 



$3.50 to 5.00 



583 Fig. 417, dipping needle, with graduated ring, . 6.00 



584 Mariner's compass, needle, and eight inch 



floating card, with mahogany stand and 



steel point, - 1.25 



585 Fig. 418, star and circular discs of soft iron, 0.50 



586 Fig. 418, soft iron rolling armature, $1 to 2.00 



587 Fig. 418, flat steel bar magnets for breaking, 



12cts. to 0.25 



588 Fig. 418, slender cylindrical rods and half 



links, per dozen, - - 2 Sets, to 0.50 



589 Fig. 418, cross bar armature, - 0.75 



590 Fig. 418, polished iron balls, - - 0.25 



591 Fig. 418, Robinson's forked or Y shaped soft 



iron armature, - 0.50 



592 Fig. 418, set of magnetic apparatus, consist- 



ing of the last seven instruments, swan and 

 fishes, magnetic needle and stand, bar 

 magnet, and horse-shoe magnet, in a box, 7.50 



593 Fig. 419, magnetic swan, fishes, &c., each, 12c. to 0.75 

 5'94 Fig. 420, magnetic Neptune, - 75 cts. to 1.00 



ELECTRO-MAGNETISM. 



595 Fig. 391, cylindrical pot battery, large size, 2.50 



596 Fig. 421, De La Rive's ring in floating battery, 1.00 



597 Fig. 422, De La Rive's ring, improved, 1.25 



598 Fig. 423, floating coil, 1.00 



599 Fig. 424, electro-magnet, three sizes, $1.00 ; 



$1.50 and - .... 2.50 



600 Fig. 425, large electro-magnet, - - $20 to 40.00 



601 Fig. 426, magic circle, four sizes, with ring 



handles, $1, $1.50, $1.75, and 2.50 



602 Magic circle, large, with ball and socket 



handles, - 7.00 



603 Fig. 427, helix and iron rod for suspension in 



the air, $1.75, $3.00, and 5.0(1 



